List of Metrics

There are two types of metrics in Alluxio, cluster-wide aggregated metrics, and per-process detailed metrics.

• Cluster metrics are collected and calculated by the leading master and displayed in the metrics tab of the web UI. These metrics are designed to provide a snapshot of the cluster state and the overall amount of data and metadata served by Alluxio.

• Process metrics are collected by each Alluxio process and exposed in a machine-readable format through any configured sinks. Process metrics are highly detailed and are intended to be consumed by third-party monitoring tools. Users can then view fine-grained dashboards with time-series graphs of each metric, such as data transferred or the number of RPC invocations.

Metrics in Alluxio have the following format for master node metrics:

Master.[metricName].[tag1].[tag2]...

Metrics in Alluxio have the following format for non-master node metrics:

[processType].[metricName].[tag1].[tag2]...[hostName]

There is generally an Alluxio metric for every RPC invocation, to Alluxio or to the under store.

Tags are additional pieces of metadata for the metric such as user name or under storage location. Tags can be used to further filter or aggregate on various characteristics.

Cluster Metrics

Workers and clients send metrics data to the Alluxio master through heartbeats. The interval is defined by property alluxio.master.worker.heartbeat.interval and alluxio.user.metrics.heartbeat.interval respectively.

Bytes metrics are aggregated value from workers or clients. Bytes throughput metrics are calculated on the leading master. The values of bytes throughput metrics equal to bytes metrics counter value divided by the metrics record time and shown as bytes per minute.

Name	Type	Description
Cluster.ActiveRpcReadCount	COUNTER	The number of active read-RPCs managed by workers
Cluster.ActiveRpcWriteCount	COUNTER	The number of active write-RPCs managed by workers
Cluster.BytesReadDirect	COUNTER	Total number of bytes read from all workers without external RPC involved. Data exists in worker storage or is fetched by workers from UFSes. This records data read by worker internal calls (e.g. clients embedded in workers).
Cluster.BytesReadDirectThroughput	GAUGE	Total number of bytes read from all workers without external RPC involved. Data exists in worker storage or is fetched by workers from UFSes. This records data read by worker internal calls (e.g. clients embedded in workers).
Cluster.BytesReadDomain	COUNTER	Total number of bytes read from all works via domain socket
Cluster.BytesReadDomainThroughput	GAUGE	Bytes read per minute throughput from all workers via domain socket
Cluster.BytesReadLocal	COUNTER	Total number of bytes short-circuit read reported by all clients. Each client reads data from the collocated worker data storage directly.
Cluster.BytesReadLocalThroughput	GAUGE	Bytes per minute throughput short-circuit read reported by all clients
Cluster.BytesReadPerUfs	COUNTER	Total number of bytes read from a specific UFS by all workers
Cluster.BytesReadRemote	COUNTER	Total number of bytes read from all workers via network (RPC). Data exists in worker storage or is fetched by workers from UFSes. This does not include short-circuit local reads and domain socket reads
Cluster.BytesReadRemoteThroughput	GAUGE	Bytes read per minute throughput from all workers via network (RPC calls). Data exists in worker storage or is fetched by workers from UFSes. This does not include short-circuit local reads and domain socket reads
Cluster.BytesReadUfsAll	COUNTER	Total number of bytes read from all Alluxio UFSes by all workers
Cluster.BytesReadUfsThroughput	GAUGE	Bytes read per minute throughput from all Alluxio UFSes by all workers
Cluster.BytesWrittenDomain	COUNTER	Total number of bytes written to all workers via domain socket
Cluster.BytesWrittenDomainThroughput	GAUGE	Throughput of bytes written per minute to all workers via domain socket
Cluster.BytesWrittenLocal	COUNTER	Total number of bytes short-circuit written to local worker data storage by all clients
Cluster.BytesWrittenLocalThroughput	GAUGE	Bytes per minute throughput written to local worker data storage by all clients
Cluster.BytesWrittenPerUfs	COUNTER	Total number of bytes written to a specific Alluxio UFS by all workers
Cluster.BytesWrittenRemote	COUNTER	Total number of bytes written to workers via network (RPC). Data is written to worker storage or is written by workers to underlying UFSes. This does not include short-circuit local writes and domain socket writes.
Cluster.BytesWrittenRemoteThroughput	GAUGE	Bytes write per minute throughput to workers via network (RPC). Data is written to worker storage or is written by workers to underlying UFSes. This does not include short-circuit local writes and domain socket writes.
Cluster.BytesWrittenUfsAll	COUNTER	Total number of bytes written to all Alluxio UFSes by all workers
Cluster.BytesWrittenUfsThroughput	GAUGE	Bytes write per minute throughput to all Alluxio UFSes by all workers
Cluster.CacheHitRate	GAUGE	Cache hit rate: (# bytes read from cache) / (# bytes requested)
Cluster.CapacityFree	GAUGE	Total free bytes on all tiers, on all workers of Alluxio
Cluster.CapacityTotal	GAUGE	Total capacity (in bytes) on all tiers, on all workers of Alluxio
Cluster.CapacityUsed	GAUGE	Total used bytes on all tiers, on all workers of Alluxio
Cluster.LeaderId	GAUGE	Display current leader id
Cluster.LeaderIndex	GAUGE	Index of current leader
Cluster.LostWorkers	GAUGE	Total number of lost workers inside the cluster
Cluster.RootUfsCapacityFree	GAUGE	Free capacity of the Alluxio root UFS in bytes
Cluster.RootUfsCapacityTotal	GAUGE	Total capacity of the Alluxio root UFS in bytes
Cluster.RootUfsCapacityUsed	GAUGE	Used capacity of the Alluxio root UFS in bytes
Cluster.Workers	GAUGE	Total number of active workers inside the cluster

Process Metrics

Metrics shared by the all Alluxio server and client processes.

Name	Type	Description
Process.pool.direct.mem.used	GAUGE	The used direct memory by NIO direct buffer pool

Server Metrics

Metrics shared by the Alluxio server processes.

Name	Type	Description
Server.JvmPauseMonitorInfoTimeExceeded	GAUGE	The total number of times that JVM slept and the sleep period is larger than the info level threshold defined by alluxio.jvm.monitor.info.threshold
Server.JvmPauseMonitorTotalExtraTime	GAUGE	The total time that JVM slept and didn't do GC
Server.JvmPauseMonitorWarnTimeExceeded	GAUGE	The total number of times that JVM slept and the sleep period is larger than the warn level threshold defined by alluxio.jvm.monitor.warn.threshold

Master Metrics

Default master metrics:

Name	Type	Description
Master.AbsentCacheHits	GAUGE	Number of cache hits on the absent cache
Master.AbsentCacheMisses	GAUGE	Number of cache misses on the absent cache
Master.AbsentCacheSize	GAUGE	Size of the absent cache
Master.AbsentPathCacheQueueSize	GAUGE	Alluxio maintains a cache of absent UFS paths. This is the number of UFS paths being processed.
Master.AsyncPersistCancel	COUNTER	The number of cancelled AsyncPersist operations
Master.AsyncPersistFail	COUNTER	The number of failed AsyncPersist operations
Master.AsyncPersistFileCount	COUNTER	The number of files created by AsyncPersist operations
Master.AsyncPersistFileSize	COUNTER	The total size of files created by AsyncPersist operations
Master.AsyncPersistSuccess	COUNTER	The number of successful AsyncPersist operations
Master.AuditLogEntriesSize	GAUGE	The size of the audit log entries blocking queue
Master.BlockHeapSize	GAUGE	An estimate of the blocks heap size
Master.BlockReplicaCount	GAUGE	Total number of block replicas in Alluxio
Master.CachedBlockLocations	GAUGE	Total number of cached block locations
Master.CompleteFileOps	COUNTER	Total number of the CompleteFile operations
Master.CompletedOperationRetryCount	COUNTER	Total number of completed operations that has been retried by client.
Master.CreateDirectoryOps	COUNTER	Total number of the CreateDirectory operations
Master.CreateFileOps	COUNTER	Total number of the CreateFile operations
Master.DeletePathOps	COUNTER	Total number of the Delete operations
Master.DirectoriesCreated	COUNTER	Total number of the succeed CreateDirectory operations
Master.EdgeCacheEvictions	GAUGE	Total number of edges (inode metadata) that was evicted from cache. The edge cache is responsible for managing the mapping from (parentId, childName) to childId.
Master.EdgeCacheHits	GAUGE	Total number of hits in the edge (inode metadata) cache. The edge cache is responsible for managing the mapping from (parentId, childName) to childId.
Master.EdgeCacheLoadTimes	GAUGE	Total load times in the edge (inode metadata) cache that resulted from a cache miss. The edge cache is responsible for managing the mapping from (parentId, childName) to childId.
Master.EdgeCacheMisses	GAUGE	Total number of misses in the edge (inode metadata) cache. The edge cache is responsible for managing the mapping from (parentId, childName) to childId.
Master.EdgeCacheSize	GAUGE	Total number of edges (inode metadata) cached. The edge cache is responsible for managing the mapping from (parentId, childName) to childId.
Master.EdgeLockPoolSize	GAUGE	The size of master edge lock pool
Master.EmbeddedJournalLastSnapshotDownloadDiskSize	GAUGE	Describes the size on disk of the snapshot downloaded from other masters in the cluster the previous time the download occurred. Only valid when using the embedded journal.
Master.EmbeddedJournalLastSnapshotDownloadDurationMs	GAUGE	Describes the amount of time taken to download journal snapshots from other masters in the cluster the previous time the download occurred. Only valid when using the embedded journal.
Master.EmbeddedJournalLastSnapshotDownloadSize	GAUGE	Describes the size of the snapshot downloaded from other masters in the cluster the previous time the download occurred. Only valid when using the embedded journal.
Master.EmbeddedJournalLastSnapshotDurationMs	GAUGE	Describes the amount of time taken to generate the last local journal snapshots on this master. Only valid when using the embedded journal.
Master.EmbeddedJournalLastSnapshotEntriesCount	GAUGE	Describes the number of entries in the last local journal snapshots on this master. Only valid when using the embedded journal.
Master.EmbeddedJournalLastSnapshotReplayDurationMs	GAUGE	Represents the time the last restore from checkpoint operation took in milliseconds.
Master.EmbeddedJournalLastSnapshotReplayEntriesCount	GAUGE	Represents the time the last restore from checkpoint operation took in milliseconds.
Master.EmbeddedJournalLastSnapshotUploadDiskSize	GAUGE	Describes the size on disk of the snapshot uploaded to other masters in the cluster the previous time the download occurred. Only valid when using the embedded journal.
Master.EmbeddedJournalLastSnapshotUploadDurationMs	GAUGE	Describes the amount of time taken to upload journal snapshots to another master in the cluster the previous time the upload occurred. Only valid when using the embedded journal.
Master.EmbeddedJournalLastSnapshotUploadSize	GAUGE	Describes the size of the snapshot uploaded to other masters in the cluster the previous time the download occurred. Only valid when using the embedded journal.
Master.EmbeddedJournalSnapshotDownloadDiskHistogram	HISTOGRAM	Describes the size on disk of the snapshot downloaded from another master in the cluster. Only valid when using the embedded journal. Long running average.
Master.EmbeddedJournalSnapshotDownloadGenerate	TIMER	Describes the amount of time taken to download journal snapshots from other masters in the cluster. Only valid when using the embedded journal. Long running average.
Master.EmbeddedJournalSnapshotDownloadHistogram	HISTOGRAM	Describes the size of the snapshot downloaded from another master in the cluster. Only valid when using the embedded journal. Long running average.
Master.EmbeddedJournalSnapshotGenerateTimer	TIMER	Describes the amount of time taken to generate local journal snapshots on this master. Only valid when using the embedded journal. Use this metric to measure the performance of Alluxio's snapshot generation.
Master.EmbeddedJournalSnapshotInstallTimer	TIMER	Describes the amount of time taken to install a downloaded journal snapshot from another master. Only valid only when using the embedded journal. Use this metric to determine the performance of Alluxio when installing snapshots from the leader. Higher numbers may indicate a slow disk or CPU contention.
Master.EmbeddedJournalSnapshotLastIndex	GAUGE	Represents the latest journal index that was recorded by this master in the most recent local snapshot or from a snapshot downloaded from another master in the cluster. Only valid when using the embedded journal.
Master.EmbeddedJournalSnapshotReplayTimer	TIMER	Describes the amount of time taken to replay a journal snapshot onto the master's state machine. Only valid only when using the embedded journal. Use this metric to determine the performance of Alluxio when replaying journal snapshot file. Higher numbers may indicate a slow disk or CPU contention
Master.EmbeddedJournalSnapshotUploadDiskHistogram	HISTOGRAM	Describes the size on disk of the snapshot uploaded to another master in the cluster. Only valid when using the embedded journal. Long running average.
Master.EmbeddedJournalSnapshotUploadHistogram	HISTOGRAM	Describes the size of the snapshot uploaded to another master in the cluster. Only valid when using the embedded journal. Long running average.
Master.EmbeddedJournalSnapshotUploadTimer	TIMER	Describes the amount of time taken to upload journal snapshots to another master in the cluster. Only valid when using the embedded journal. long running average
Master.FileBlockInfosGot	COUNTER	Total number of succeed GetFileBlockInfo operations
Master.FileInfosGot	COUNTER	Total number of the succeed GetFileInfo operations
Master.FileSize	GAUGE	File size distribution
Master.FilesCompleted	COUNTER	Total number of the succeed CompleteFile operations
Master.FilesCreated	COUNTER	Total number of the succeed CreateFile operations
Master.FilesFreed	COUNTER	Total number of succeed FreeFile operations
Master.FilesPersisted	COUNTER	Total number of successfully persisted files
Master.FilesPinned	GAUGE	Total number of currently pinned files. Note that IDs for these files are stored in memory.
Master.FilesToBePersisted	GAUGE	Total number of currently to be persisted files. Note that the IDs for these files are stored in memory.
Master.FreeFileOps	COUNTER	Total number of FreeFile operations
Master.GetFileBlockInfoOps	COUNTER	Total number of GetFileBlockInfo operations
Master.GetFileInfoOps	COUNTER	Total number of the GetFileInfo operations
Master.GetNewBlockOps	COUNTER	Total number of the GetNewBlock operations
Master.InodeCacheEvictions	GAUGE	Total number of inodes that was evicted from the cache.
Master.InodeCacheHitRatio	GAUGE	Inode Cache hit ratio
Master.InodeCacheHits	GAUGE	Total number of hits in the inodes (inode metadata) cache.
Master.InodeCacheLoadTimes	GAUGE	Total load times in the inodes (inode metadata) cache that resulted from a cache miss.
Master.InodeCacheMisses	GAUGE	Total number of misses in the inodes (inode metadata) cache.
Master.InodeCacheSize	GAUGE	Total number of inodes (inode metadata) cached.
Master.InodeHeapSize	GAUGE	An estimate of the inode heap size
Master.InodeLockPoolSize	GAUGE	The size of master inode lock pool
Master.JobCanceled	COUNTER	The number of canceled status job
Master.JobCompleted	COUNTER	The number of completed status job
Master.JobCount	GAUGE	The number of all status job
Master.JobCreated	COUNTER	The number of created status job
Master.JobDistributedLoadBlockSizes	COUNTER	The total block size loaded by load commands
Master.JobDistributedLoadCancel	COUNTER	The number of cancelled DistributedLoad operations
Master.JobDistributedLoadFail	COUNTER	The number of failed DistributedLoad operations
Master.JobDistributedLoadFileCount	COUNTER	The number of files by DistributedLoad operations
Master.JobDistributedLoadFileSizes	COUNTER	The total file size by DistributedLoad operations
Master.JobDistributedLoadRate	METER	The average DistributedLoad loading rate
Master.JobDistributedLoadSuccess	COUNTER	The number of successful DistributedLoad operations
Master.JobFailed	COUNTER	The number of failed status job
Master.JobLoadBlockCount	COUNTER	The number of blocks loaded by load commands
Master.JobLoadBlockFail	COUNTER	The number of blocks failed to be loaded by load commands
Master.JobLoadFail	COUNTER	The number of failed Load commands
Master.JobLoadRate	METER	The average loading rate of Load commands
Master.JobLoadSuccess	COUNTER	The number of successful Load commands
Master.JobRunning	COUNTER	The number of running status job
Master.JournalCheckpointWarn	GAUGE	If the raft log index exceeds alluxio.master.journal.checkpoint.period.entries, and the last checkpoint exceeds alluxio.master.journal.checkpoint.warning.threshold.time, it returns 1 to indicate that a warning is required, otherwise it returns 0
Master.JournalEntriesSinceCheckPoint	GAUGE	Journal entries since last checkpoint
Master.JournalFlushFailure	COUNTER	Total number of failed journal flush
Master.JournalFlushTimer	TIMER	The timer statistics of journal flush
Master.JournalFreeBytes	GAUGE	Bytes left on the journal disk(s) for an Alluxio master. This metric is only valid on Linux and when embedded journal is used. Use this metric to monitor whether your journal is running out of disk space.
Master.JournalFreePercent	GAUGE	Percentage of free space left on the journal disk(s) for an Alluxio master.This metric is only valid on Linux and when embedded journal is used. Use this metric to monitor whether your journal is running out of disk space.
Master.JournalGainPrimacyTimer	TIMER	The timer statistics of journal gain primacy
Master.JournalLastAppliedCommitIndex	GAUGE	The last raft log index which was applied to the state machine
Master.JournalLastCheckPointTime	GAUGE	Last Journal Checkpoint Time
Master.JournalSequenceNumber	GAUGE	Current journal sequence number
Master.LastBackupEntriesCount	GAUGE	The total number of entries written in the last leading master metadata backup
Master.LastBackupRestoreCount	GAUGE	The total number of entries restored from backup when a leading master initializes its metadata
Master.LastBackupRestoreTimeMs	GAUGE	The process time of the last restore from backup
Master.LastBackupTimeMs	GAUGE	The process time of the last backup
Master.LastGainPrimacyTime	GAUGE	Last time the master gains primacy
Master.LastLosePrimacyTime	GAUGE	Last time the master loses primacy
Master.ListingCacheEvictions	COUNTER	The total number of evictions in master listing cache
Master.ListingCacheHits	COUNTER	The total number of hits in master listing cache
Master.ListingCacheLoadTimes	COUNTER	The total load time (in nanoseconds) in master listing cache that resulted from a cache miss.
Master.ListingCacheMisses	COUNTER	The total number of misses in master listing cache
Master.ListingCacheSize	GAUGE	The size of master listing cache
Master.LostBlockCount	GAUGE	Count of lost unique blocks
Master.LostFileCount	GAUGE	Count of lost files. This number is cached and may not be in sync with Master.LostBlockCount
Master.MetadataSyncActivePaths	COUNTER	The number of in-progress paths from all InodeSyncStream instances
Master.MetadataSyncExecutor	EXECUTOR_SERVICE	Metrics concerning the master metadata sync executor threads. Master.MetadataSyncExecutor.submitted is a meter of the tasks submitted to the executor. Master.MetadataSyncExecutor.completed is a meter of the tasks completed by the executor. Master.MetadataSyncExecutor.activeTaskQueue is exponentially-decaying random reservoir of the number of active tasks (running or submitted) at the executor calculated each time a new task is added to the executor. The max value is the maximum number of active tasks at any time during execution. Master.MetadataSyncExecutor.running is the number of tasks actively being run by the executor. Master.MetadataSyncExecutor.idle is the time spent idling by the submitted tasks (i.e. waiting the the queue before being executed). Master.MetadataSyncExecutor.duration is the time spent running the submitted tasks. If the executor is a thread pool executor then Master.MetadataSyncExecutor.queueSize is the size of the task queue.
Master.MetadataSyncExecutorQueueSize	GAUGE	The number of queuing sync tasks in the metadata sync thread pool controlled by alluxio.master.metadata.sync.executor.pool.size
Master.MetadataSyncFail	COUNTER	The number of InodeSyncStream that failed, either partially or fully
Master.MetadataSyncNoChange	COUNTER	The number of InodeSyncStream that finished with no change to inodes.
Master.MetadataSyncOpsCount	COUNTER	The number of metadata sync operations. Each sync operation corresponds to one InodeSyncStream instance.
Master.MetadataSyncPathsCancel	COUNTER	The number of pending paths from all InodeSyncStream instances that are ignored in the end instead of processed
Master.MetadataSyncPathsFail	COUNTER	The number of paths that failed during metadata sync from all InodeSyncStream instances
Master.MetadataSyncPathsSuccess	COUNTER	The number of paths sync-ed from all InodeSyncStream instances
Master.MetadataSyncPendingPaths	COUNTER	The number of pending paths from all active InodeSyncStream instances,waiting for metadata sync
Master.MetadataSyncPrefetchCancel	COUNTER	Number of cancelled prefetch jobs from metadata sync
Master.MetadataSyncPrefetchExecutor	EXECUTOR_SERVICE	Metrics concerning the master metadata sync prefetchexecutor threads. Master.MetadataSyncPrefetchExecutor.submitted is a meter of the tasks submitted to the executor. Master.MetadataSyncPrefetchExecutor.completed is a meter of the tasks completed by the executor. Master.MetadataSyncPrefetchExecutor.activeTaskQueue is exponentially-decaying random reservoir of the number of active tasks (running or submitted) at the executor calculated each time a new task is added to the executor. The max value is the maximum number of active tasks at any time during execution. Master.MetadataSyncPrefetchExecutor.running is the number of tasks actively being run by the executor. Master.MetadataSyncPrefetchExecutor.idle is the time spent idling by the submitted tasks (i.e. waiting the the queue before being executed). Master.MetadataSyncPrefetchExecutor.duration is the time spent running the submitted tasks. If the executor is a thread pool executor then Master.MetadataSyncPrefetchExecutor.queueSize is the size of the task queue.
Master.MetadataSyncPrefetchExecutorQueueSize	GAUGE	The number of queuing prefetch tasks in the metadata sync thread pool controlled by alluxio.master.metadata.sync.ufs.prefetch.pool.size
Master.MetadataSyncPrefetchFail	COUNTER	Number of failed prefetch jobs from metadata sync
Master.MetadataSyncPrefetchOpsCount	COUNTER	The number of prefetch operations handled by the prefetch thread pool
Master.MetadataSyncPrefetchPaths	COUNTER	Total number of UFS paths fetched by prefetch jobs from metadata sync
Master.MetadataSyncPrefetchRetries	COUNTER	Number of retries to get from prefetch jobs from metadata sync
Master.MetadataSyncPrefetchSuccess	COUNTER	Number of successful prefetch jobs from metadata sync
Master.MetadataSyncSkipped	COUNTER	The number of InodeSyncStream that are skipped because the Alluxio metadata is fresher than alluxio.user.file.metadata.sync.interval
Master.MetadataSyncSuccess	COUNTER	The number of InodeSyncStream that succeeded
Master.MetadataSyncTimeMs	COUNTER	The total time elapsed in all InodeSyncStream instances
Master.MetadataSyncUfsMount.	COUNTER	The number of UFS sync operations for a given mount point
Master.MigrateJobCancel	COUNTER	The number of cancelled MigrateJob operations
Master.MigrateJobFail	COUNTER	The number of failed MigrateJob operations
Master.MigrateJobFileCount	COUNTER	The number of MigrateJob files
Master.MigrateJobFileSize	COUNTER	The total size of MigrateJob files
Master.MigrateJobSuccess	COUNTER	The number of successful MigrateJob operations
Master.MountOps	COUNTER	Total number of Mount operations
Master.NewBlocksGot	COUNTER	Total number of the succeed GetNewBlock operations
Master.PathsDeleted	COUNTER	Total number of the succeed Delete operations
Master.PathsMounted	COUNTER	Total number of succeed Mount operations
Master.PathsRenamed	COUNTER	Total number of succeed Rename operations
Master.PathsUnmounted	COUNTER	Total number of succeed Unmount operations
Master.RenamePathOps	COUNTER	Total number of Rename operations
Master.ReplicaMgmtActiveJobSize	GAUGE	Number of active block replication/eviction jobs. These jobs are created by the master to maintain the block replica factor. The value is an estimate with lag.
Master.ReplicationLimitedFiles	COUNTER	Number of files that have a replication count set to a non-default value. Note that these files have IDs that are stored in memory.
Master.RocksBlockBackgroundErrors	GAUGE	RocksDB block table. Accumulated number of background errors.
Master.RocksBlockBlockCacheCapacity	GAUGE	RocksDB block table. Block cache capacity.
Master.RocksBlockBlockCachePinnedUsage	GAUGE	RocksDB block table. Memory size for the entries being pinned.
Master.RocksBlockBlockCacheUsage	GAUGE	RocksDB block table. Memory size for the entries residing in block cache.
Master.RocksBlockCompactionPending	GAUGE	RocksDB block table. This metric 1 if at least one compaction is pending; otherwise, the metric reports 0.
Master.RocksBlockCurSizeActiveMemTable	GAUGE	RocksDB block table. Approximate size of active memtable in bytes.
Master.RocksBlockCurSizeAllMemTables	GAUGE	RocksDB block table. Approximate size of active, unflushed immutable, and pinned immutable memtables in bytes. Pinned immutable memtables are flushed memtables that are kept in memory to maintain write history in memory.
Master.RocksBlockEstimateNumKeys	GAUGE	RocksDB block table. Estimated number of total keys in the active and unflushed immutable memtables and storage.
Master.RocksBlockEstimatePendingCompactionBytes	GAUGE	RocksDB block table. Estimated total number of bytes a compaction needs to rewrite on disk to get all levels down to under target size. In other words, this metrics relates to the write amplification in level compaction. Thus, this metric is not valid for compactions other than level-based.
Master.RocksBlockEstimateTableReadersMem	GAUGE	RocksDB inode table. Estimated memory in bytes used for reading SST tables, excluding memory used in block cache (e.g., filter and index blocks). This metric records the memory used by iterators as well as filters and indices if the filters and indices are not maintained in the block cache. Basically this metric reports the memory used outside the block cache to read data.
Master.RocksBlockEstimatedMemUsage	GAUGE	RocksDB block table. This metric estimates the memory usage of the RockDB Block table by aggregating the values of Master.RocksBlockBlockCacheUsage, Master.RocksBlockEstimateTableReadersMem, Master.RocksBlockCurSizeAllMemTables, and Master.RocksBlockBlockCachePinnedUsage
Master.RocksBlockLiveSstFilesSize	GAUGE	RocksDB block table. Total size in bytes of all SST files that belong to the latest LSM tree.
Master.RocksBlockMemTableFlushPending	GAUGE	RocksDB block table. This metric returns 1 if a memtable flush is pending; otherwhise it returns 0.
Master.RocksBlockNumDeletesActiveMemTable	GAUGE	RocksDB block table. Total number of delete entries in the active memtable.
Master.RocksBlockNumDeletesImmMemTables	GAUGE	RocksDB block table. Total number of delete entries in the unflushed immutable memtables.
Master.RocksBlockNumEntriesActiveMemTable	GAUGE	RocksDB block table. Total number of entries in the active memtable.
Master.RocksBlockNumEntriesImmMemTables	GAUGE	RocksDB block table. Total number of entries in the unflushed immutable memtables.
Master.RocksBlockNumImmutableMemTable	GAUGE	RocksDB block table. Number of immutable memtables that have not yet been flushed.
Master.RocksBlockNumLiveVersions	GAUGE	RocksDB inode table. Number of live versions. More live versions often mean more SST files are held from being deleted, by iterators or unfinished compactions.
Master.RocksBlockNumRunningCompactions	GAUGE	RocksDB block table. Number of currently running compactions.
Master.RocksBlockNumRunningFlushes	GAUGE	RocksDB block table. Number of currently running flushes.
Master.RocksBlockSizeAllMemTables	GAUGE	RocksDB block table. Size all mem tables.
Master.RocksBlockTotalSstFilesSize	GAUGE	RocksDB block table. Total size in bytes of all SST files.
Master.RocksInodeBackgroundErrors	GAUGE	RocksDB inode table. Accumulated number of background errors.
Master.RocksInodeBlockCacheCapacity	GAUGE	RocksDB inode table. Block cache capacity.
Master.RocksInodeBlockCachePinnedUsage	GAUGE	RocksDB inode table. Memory size for the entries being pinned.
Master.RocksInodeBlockCacheUsage	GAUGE	RocksDB inode table. Memory size for the entries residing in block cache.
Master.RocksInodeCompactionPending	GAUGE	RocksDB inode table. This metric 1 if at least one compaction is pending; otherwise, the metric reports 0.
Master.RocksInodeCurSizeActiveMemTable	GAUGE	RocksDB inode table. Approximate size of active memtable in bytes.
Master.RocksInodeCurSizeAllMemTables	GAUGE	RocksDB inode table. Approximate size of active and unflushed immutable memtable in bytes.
Master.RocksInodeEstimateNumKeys	GAUGE	RocksDB inode table. Estimated number of total keys in the active and unflushed immutable memtables and storage.
Master.RocksInodeEstimatePendingCompactionBytes	GAUGE	RocksDB block table. Estimated total number of bytes a compaction needs to rewrite on disk to get all levels down to under target size. In other words, this metrics relates to the write amplification in level compaction. Thus, this metric is not valid for compactions other than level-based.
Master.RocksInodeEstimateTableReadersMem	GAUGE	RocksDB inode table. Estimated memory in bytes used for reading SST tables, excluding memory used in block cache (e.g., filter and index blocks). This metric records the memory used by iterators as well as filters and indices if the filters and indices are not maintained in the block cache. Basically this metric reports the memory used outside the block cache to read data.
Master.RocksInodeEstimatedMemUsage	GAUGE	RocksDB block table. This metric estimates the memory usage of the RockDB Inode table by aggregating the values of Master.RocksInodeBlockCacheUsage, Master.RocksInodeEstimateTableReadersMem, Master.RocksInodeCurSizeAllMemTables, and Master.RocksInodeBlockCachePinnedUsage
Master.RocksInodeLiveSstFilesSize	GAUGE	RocksDB inode table. Total size in bytes of all SST files that belong to the latest LSM tree.
Master.RocksInodeMemTableFlushPending	GAUGE	RocksDB inode table. This metric returns 1 if a memtable flush is pending; otherwhise it returns 0.
Master.RocksInodeNumDeletesActiveMemTable	GAUGE	RocksDB inode table. Total number of delete entries in the active memtable.
Master.RocksInodeNumDeletesImmMemTables	GAUGE	RocksDB inode table. Total number of delete entries in the unflushed immutable memtables.
Master.RocksInodeNumEntriesActiveMemTable	GAUGE	RocksDB inode table. Total number of entries in the active memtable.
Master.RocksInodeNumEntriesImmMemTables	GAUGE	RocksDB inode table. Total number of entries in the unflushed immutable memtables.
Master.RocksInodeNumImmutableMemTable	GAUGE	RocksDB inode table. Number of immutable memtables that have not yet been flushed.
Master.RocksInodeNumLiveVersions	GAUGE	RocksDB inode table. Number of live versions. More live versions often mean more SST files are held from being deleted, by iterators or unfinished compactions.
Master.RocksInodeNumRunningCompactions	GAUGE	RocksDB inode table. Number of currently running compactions.
Master.RocksInodeNumRunningFlushes	GAUGE	RocksDB inode table. Number of currently running flushes.
Master.RocksInodeSizeAllMemTables	GAUGE	RocksDB inode table. Approximate size of active, unflushed immutable, and pinned immutable memtables in bytes. Pinned immutable memtables are flushed memtables that are kept in memory to maintain write history in memory.
Master.RocksInodeTotalSstFilesSize	GAUGE	RocksDB inode table. Total size in bytes of all SST files.
Master.RocksTotalEstimatedMemUsage	GAUGE	This metric gives an estimate of the total memory used by RocksDB by aggregating the values of Master.RocksBlockEstimatedMemUsage and Master.RocksInodeEstimatedMemUsage
Master.RoleId	GAUGE	Display master role id
Master.RpcQueueLength	GAUGE	Length of the master rpc queue. Use this metric to monitor the RPC pressure on master.
Master.RpcThreadActiveCount	GAUGE	The number of threads that are actively executing tasks in the master RPC executor thread pool. Use this metric to monitor the RPC pressure on master.
Master.RpcThreadCurrentCount	GAUGE	Current count of threads in the master RPC executor thread pool. Use this metric to monitor the RPC pressure on master.
Master.SetAclOps	COUNTER	Total number of SetAcl operations
Master.SetAttributeOps	COUNTER	Total number of SetAttribute operations
Master.StartTime	GAUGE	The start time of the master process
Master.TTLBuckets	GAUGE	The number of TTL buckets at the master. Note that these buckets are stored in memory.
Master.TTLInodes	GAUGE	The total number of inodes contained in TTL buckets at the mater. Note that these inodes are stored in memory.
Master.ToRemoveBlockCount	GAUGE	Count of block replicas to be removed from the workers. If 1 block is to be removed from 2 workers, 2 will be counted here.
Master.TotalPaths	GAUGE	Total number of files and directory in Alluxio namespace
Master.TotalRpcs	TIMER	Throughput of master RPC calls. This metrics indicates how busy the master is serving client and worker requests
Master.UfsJournalCatchupTimer	TIMER	The timer statistics of journal catchupOnly valid when ufs journal is used. This provides a summary of how long a standby master takes to catch up with primary master, and should be monitored if master transition takes too long
Master.UfsJournalFailureRecoverTimer	TIMER	The timer statistics of ufs journal failure recover
Master.UfsJournalInitialReplayTimeMs	GAUGE	The process time of the ufs journal initial replay.Only valid when ufs journal is used. It records the time it took for the very first journal replay. Use this metric to monitor when your master boot-up time is high。
Master.UfsStatusCacheChildrenSize	COUNTER	Total number of UFS file metadata cached. The cache is used during metadata sync.
Master.UfsStatusCacheSize	COUNTER	Total number of Alluxio paths being processed by the metadata sync prefetch thread pool.
Master.UniqueBlocks	GAUGE	Total number of unique blocks in Alluxio
Master.UnmountOps	COUNTER	Total number of Unmount operations

Dynamically generated master metrics:

Metric Name	Description
Master.CapacityTotalTier{TIER_NAME}	Total capacity in tier {TIER_NAME} of the Alluxio file system in bytes
Master.CapacityUsedTier{TIER_NAME}	Used capacity in tier {TIER_NAME} of the Alluxio file system in bytes
Master.CapacityFreeTier{TIER_NAME}	Free capacity in tier {TIER_NAME} of the Alluxio file system in bytes
Master.UfsSessionCount-Ufs:{UFS_ADDRESS}	The total number of currently opened UFS sessions to connect to the given {UFS_ADDRESS}
Master.{UFS_RPC_NAME}.UFS:{UFS_ADDRESS}.UFS_TYPE:{UFS_TYPE}.User:{USER}	The details UFS rpc operation done by the current master
Master.PerUfsOp{UFS_RPC_NAME}.UFS:{UFS_ADDRESS}	The aggregated number of UFS operation {UFS_RPC_NAME} ran on UFS {UFS_ADDRESS} by leading master
Master.{LEADING_MASTER_RPC_NAME}	The duration statistics of RPC calls exposed on leading master

Worker Metrics

Default worker metrics:

Name	Type	Description
Worker.ActiveClients	COUNTER	The number of clients actively reading from or writing to this worker
Worker.ActiveRpcReadCount	COUNTER	The number of active read-RPCs managed by this worker
Worker.ActiveRpcWriteCount	COUNTER	The number of active write-RPCs managed by this worker
Worker.BlockReaderCompleteTaskCount	GAUGE	The approximate total number of block read tasks that have completed execution
Worker.BlockReaderThreadActiveCount	GAUGE	The approximate number of block read threads that are actively executing tasks in reader thread pool
Worker.BlockReaderThreadCurrentCount	GAUGE	The current number of read threads in the reader thread pool
Worker.BlockReaderThreadMaxCount	GAUGE	The maximum allowed number of block read thread in the reader thread pool
Worker.BlockRemoverBlocksRemovedCount	COUNTER	The total number of blocks successfully removed from this worker by asynchronous block remover.
Worker.BlockRemoverRemovingBlocksSize	GAUGE	The size of blocks is being removed from this worker at a moment by asynchronous block remover.
Worker.BlockRemoverTryRemoveBlocksSize	GAUGE	The number of blocks to be removed from this worker at a moment by asynchronous block remover.
Worker.BlockRemoverTryRemoveCount	COUNTER	The total number of blocks this worker attempted to remove with asynchronous block remover.
Worker.BlockSerializedCompleteTaskCount	GAUGE	The approximate total number of block serialized tasks that have completed execution
Worker.BlockSerializedThreadActiveCount	GAUGE	The approximate number of block serialized threads that are actively executing tasks in serialized thread pool
Worker.BlockSerializedThreadCurrentCount	GAUGE	The current number of serialized threads in the serialized thread pool
Worker.BlockSerializedThreadMaxCount	GAUGE	The maximum allowed number of block serialized thread in the serialized thread pool
Worker.BlockWriterCompleteTaskCount	GAUGE	The approximate total number of block write tasks that have completed execution
Worker.BlockWriterThreadActiveCount	GAUGE	The approximate number of block write threads that are actively executing tasks in writer thread pool
Worker.BlockWriterThreadCurrentCount	GAUGE	The current number of write threads in the writer thread pool
Worker.BlockWriterThreadMaxCount	GAUGE	The maximum allowed number of block write thread in the writer thread pool
Worker.BlocksAccessed	COUNTER	Total number of times any one of the blocks in this worker is accessed.
Worker.BlocksCached	GAUGE	Total number of blocks used for caching data in an Alluxio worker
Worker.BlocksCancelled	COUNTER	Total number of aborted temporary blocks in this worker.
Worker.BlocksDeleted	COUNTER	Total number of deleted blocks in this worker by external requests.
Worker.BlocksEvicted	COUNTER	Total number of evicted blocks in this worker.
Worker.BlocksEvictionRate	METER	Block eviction rate in this worker.
Worker.BlocksLost	COUNTER	Total number of lost blocks in this worker.
Worker.BlocksPromoted	COUNTER	Total number of times any one of the blocks in this worker moved to a new tier.
Worker.BlocksReadLocal	COUNTER	Total number of local blocks read by this worker.
Worker.BlocksReadRemote	COUNTER	Total number of a remote blocks read by this worker.
Worker.BlocksReadUfs	COUNTER	Total number of a UFS blocks read by this worker.
Worker.BytesReadDirect	COUNTER	Total number of bytes read from the this worker without external RPC involved. Data exists in worker storage or is fetched by this worker from underlying UFSes. This records data read by worker internal calls (e.g. a client embedded in this worker).
Worker.BytesReadDirectThroughput	METER	Throughput of bytes read from the this worker without external RPC involved. Data exists in worker storage or is fetched by this worker from underlying UFSes. This records data read by worker internal calls (e.g. a client embedded in this worker).
Worker.BytesReadDomain	COUNTER	Total number of bytes read from the this worker via domain socket
Worker.BytesReadDomainThroughput	METER	Bytes read throughput from the this worker via domain socket
Worker.BytesReadPerUfs	COUNTER	Total number of bytes read from a specific Alluxio UFS by this worker
Worker.BytesReadRemote	COUNTER	Total number of bytes read from the this worker via network (RPC). Data exists in worker storage or is fetched by this worker from underlying UFSes. This does not include short-circuit local reads and domain socket reads.
Worker.BytesReadRemoteThroughput	METER	Throughput of bytes read from the this worker via network (RPC). Data exists in worker storage or is fetched by this worker from underlying UFSes. This does not include short-circuit local reads and domain socket reads
Worker.BytesReadUfsThroughput	METER	Bytes read throughput from all Alluxio UFSes by this worker
Worker.BytesWrittenDirect	COUNTER	Total number of bytes written to this worker without external RPC involved. Data is written to worker storage or is written by this worker to underlying UFSes. This records data written by worker internal calls (e.g. a client embedded in this worker).
Worker.BytesWrittenDirectThroughput	METER	Total number of bytes written to this worker without external RPC involved. Data is written to worker storage or is written by this worker to underlying UFSes. This records data written by worker internal calls (e.g. a client embedded in this worker).
Worker.BytesWrittenDomain	COUNTER	Total number of bytes written to this worker via domain socket
Worker.BytesWrittenDomainThroughput	METER	Throughput of bytes written to this worker via domain socket
Worker.BytesWrittenPerUfs	COUNTER	Total number of bytes written to a specific Alluxio UFS by this worker
Worker.BytesWrittenRemote	COUNTER	Total number of bytes written to this worker via network (RPC). Data is written to worker storage or is written by this worker to underlying UFSes. This does not include short-circuit local writes and domain socket writes.
Worker.BytesWrittenRemoteThroughput	METER	Bytes write throughput to this worker via network (RPC). Data is written to worker storage or is written by this worker to underlying UFSes. This does not include short-circuit local writes and domain socket writes.
Worker.BytesWrittenUfsThroughput	METER	Bytes write throughput to all Alluxio UFSes by this worker
Worker.CacheBlocksSize	COUNTER	Total number of bytes that being cached through cache requests
Worker.CacheFailedBlocks	COUNTER	Total number of failed cache blocks in this worker
Worker.CacheManagerCompleteTaskCount	GAUGE	The approximate total number of block cache tasks that have completed execution
Worker.CacheManagerThreadActiveCount	GAUGE	The approximate number of block cache threads that are actively executing tasks in the cache manager thread pool
Worker.CacheManagerThreadCurrentCount	GAUGE	The current number of cache threads in the cache manager thread pool
Worker.CacheManagerThreadMaxCount	GAUGE	The maximum allowed number of block cache thread in the cache manager thread pool
Worker.CacheManagerThreadQueueWaitingTaskCount	GAUGE	The current number of tasks waiting in the work queue in the cache manager thread pool, bounded by alluxio.worker.network.async.cache.manager.queue.max
Worker.CacheRemoteBlocks	COUNTER	Total number of blocks that need to be cached from remote source
Worker.CacheRequests	COUNTER	Total number of cache request received by this worker
Worker.CacheRequestsAsync	COUNTER	Total number of async cache request received by this worker
Worker.CacheRequestsSync	COUNTER	Total number of sync cache request received by this worker
Worker.CacheSucceededBlocks	COUNTER	Total number of cache succeeded blocks in this worker
Worker.CacheUfsBlocks	COUNTER	Total number of blocks that need to be cached from local source
Worker.CapacityFree	GAUGE	Total free bytes on all tiers of a specific Alluxio worker
Worker.CapacityTotal	GAUGE	Total capacity (in bytes) on all tiers of a specific Alluxio worker
Worker.CapacityUsed	GAUGE	Total used bytes on all tiers of a specific Alluxio worker
Worker.MasterRegistrationSuccessCount	COUNTER	Total number of the succeed master registration.
Worker.RpcQueueLength	GAUGE	Length of the worker rpc queue. Use this metric to monitor the RPC pressure on worker.
Worker.RpcThreadActiveCount	GAUGE	The number of threads that are actively executing tasks in the worker RPC executor thread pool. Use this metric to monitor the RPC pressure on worker.
Worker.RpcThreadCurrentCount	GAUGE	Current count of threads in the worker RPC executor thread pool. Use this metric to monitor the RPC pressure on worker.

Dynamically generated worker metrics:

Metric Name	Description
Worker.UfsSessionCount-Ufs:{UFS_ADDRESS}	The total number of currently opened UFS sessions to connect to the given {UFS_ADDRESS}
Worker.{RPC_NAME}	The duration statistics of RPC calls exposed on workers

Client Metrics

Each client metric will be recorded with its local hostname or alluxio.user.app.id is configured. If alluxio.user.app.id is configured, multiple clients can be combined into a logical application.

Name	Type	Description
Client.BlockMasterClientCount	COUNTER	Number of instances in the BlockMasterClientPool.
Client.BlockReadChunkRemote	TIMER	The timer statistics of reading block data in chunks from remote Alluxio workers via RPC framework. This metrics will only be recorded when alluxio.user.block.read.metrics.enabled is set to true
Client.BlockWorkerClientCount	COUNTER	Number of instances in the BlockWorkerClientPool.
Client.BusyExceptionCount	COUNTER	Total number of BusyException observed
Client.BytesReadLocal	COUNTER	Total number of bytes short-circuit read from worker data storage that collocates with the client
Client.BytesReadLocalThroughput	METER	Bytes throughput short-circuit read from worker data storage that collocated with this client
Client.BytesWrittenLocal	COUNTER	Total number of bytes short-circuit written to local storage by this client
Client.BytesWrittenLocalThroughput	METER	Bytes throughput short-circuit written to local storage by this client
Client.BytesWrittenUfs	COUNTER	Total number of bytes write to Alluxio UFS by this client
Client.CacheBytesDiscarded	METER	Total number of bytes discarded when restoring the page store.
Client.CacheBytesEvicted	METER	Total number of bytes evicted from the client cache.
Client.CacheBytesReadCache	METER	Total number of bytes read from the client cache.
Client.CacheBytesReadExternal	METER	Total number of bytes read from external storage due to a cache miss on the client cache.
Client.CacheBytesReadInStreamBuffer	METER	Total number of bytes read from the client cache's in stream buffer.
Client.CacheBytesRequestedExternal	METER	Total number of bytes the user requested to read which resulted in a cache miss. This number may be smaller than Client.CacheBytesReadExternal due to chunk reads.
Client.CacheBytesWrittenCache	METER	Total number of bytes written to the client cache.
Client.CacheCleanErrors	COUNTER	Number of failures when cleaning out the existing cache directory to initialize a new cache.
Client.CacheCleanupGetErrors	COUNTER	Number of failures when cleaning up a failed cache read.
Client.CacheCleanupPutErrors	COUNTER	Number of failures when cleaning up a failed cache write.
Client.CacheCreateErrors	COUNTER	Number of failures when creating a cache in the client cache.
Client.CacheDeleteErrors	COUNTER	Number of failures when deleting cached data in the client cache.
Client.CacheDeleteFromStoreErrors	COUNTER	Number of failures when deleting pages from page stores.
Client.CacheDeleteNonExistingPageErrors	COUNTER	Number of failures when deleting pages due to absence.
Client.CacheDeleteNotReadyErrors	COUNTER	Number of failures when cache is not ready to delete pages.
Client.CacheGetErrors	COUNTER	Number of failures when getting cached data in the client cache.
Client.CacheGetNotReadyErrors	COUNTER	Number of failures when cache is not ready to get pages.
Client.CacheGetStoreReadErrors	COUNTER	Number of failures when getting cached data in the client cache due to failed read from page stores.
Client.CacheHitRate	GAUGE	Cache hit rate: (# bytes read from cache) / (# bytes requested).
Client.CachePageReadCacheTimeNanos	METER	Time in nanoseconds taken to read a page from the client cache when the cache hits.
Client.CachePageReadExternalTimeNanos	METER	Time in nanoseconds taken to read a page from external source when the cache misses.
Client.CachePages	COUNTER	Total number of pages in the client cache.
Client.CachePagesDiscarded	METER	Total number of pages discarded when restoring the page store.
Client.CachePagesEvicted	METER	Total number of pages evicted from the client cache.
Client.CachePutAsyncRejectionErrors	COUNTER	Number of failures when putting cached data in the client cache due to failed injection to async write queue.
Client.CachePutBenignRacingErrors	COUNTER	Number of failures when adding pages due to racing eviction. This error is benign.
Client.CachePutErrors	COUNTER	Number of failures when putting cached data in the client cache.
Client.CachePutEvictionErrors	COUNTER	Number of failures when putting cached data in the client cache due to failed eviction.
Client.CachePutInsufficientSpaceErrors	COUNTER	Number of failures when putting cached data in the client cache due to insufficient space made after eviction.
Client.CachePutNotReadyErrors	COUNTER	Number of failures when cache is not ready to add pages.
Client.CachePutStoreDeleteErrors	COUNTER	Number of failures when putting cached data in the client cache due to failed deletes in page store.
Client.CachePutStoreWriteErrors	COUNTER	Number of failures when putting cached data in the client cache due to failed writes to page store.
Client.CachePutStoreWriteNoSpaceErrors	COUNTER	Number of failures when putting cached data in the client cache but getting disk is full while cache capacity is not achieved. This can happen if the storage overhead ratio to write data is underestimated.
Client.CacheShadowCacheBytes	COUNTER	Amount of bytes in the client shadow cache.
Client.CacheShadowCacheBytesHit	COUNTER	Total number of bytes hit the client shadow cache.
Client.CacheShadowCacheBytesRead	COUNTER	Total number of bytes read from the client shadow cache.
Client.CacheShadowCacheFalsePositiveRatio	COUNTER	Probability that the working set bloom filter makes an error. The value is 0-100. If too high, need to allocate more space
Client.CacheShadowCachePages	COUNTER	Amount of pages in the client shadow cache.
Client.CacheShadowCachePagesHit	COUNTER	Total number of pages hit the client shadow cache.
Client.CacheShadowCachePagesRead	COUNTER	Total number of pages read from the client shadow cache.
Client.CacheSpaceAvailable	GAUGE	Amount of bytes available in the client cache.
Client.CacheSpaceUsed	GAUGE	Amount of bytes used by the client cache.
Client.CacheSpaceUsedCount	COUNTER	Amount of bytes used by the client cache as a counter.
Client.CacheState	COUNTER	State of the cache: 0 (NOT_IN_USE), 1 (READ_ONLY) and 2 (READ_WRITE)
Client.CacheStoreDeleteTimeout	COUNTER	Number of timeouts when deleting pages from page store.
Client.CacheStoreGetTimeout	COUNTER	Number of timeouts when reading pages from page store.
Client.CacheStorePutTimeout	COUNTER	Number of timeouts when writing new pages to page store.
Client.CacheStoreThreadsRejected	COUNTER	Number of rejection of I/O threads on submitting tasks to thread pool, likely due to unresponsive local file system.
Client.CloseAlluxioOutStreamLatency	TIMER	Latency of close Alluxio outstream latency
Client.CloseUFSOutStreamLatency	TIMER	Latency of close UFS outstream latency
Client.DefaultHiveClientCount	COUNTER	Number of instances in the DefaultHiveClientPool.
Client.FileSystemMasterClientCount	COUNTER	Number of instances in the FileSystemMasterClientPool.
Client.MetadataCacheSize	GAUGE	The total number of files and directories whose metadata is cached on the client-side. Only valid if the filesystem is alluxio.client.file.MetadataCachingBaseFileSystem.

Fuse Metrics

Fuse is a long-running Alluxio client. Depending on the launching ways, Fuse metrics show as

• client metrics when Fuse client is launching in a standalone AlluxioFuse process.

• worker metrics when Fuse client is embedded in the AlluxioWorker process.

Fuse metrics includes:

Name	Type	Description
Fuse.CachedPathCount	GAUGE	Total number of FUSE-to-Alluxio path mappings being cached. This value will be smaller or equal to alluxio.fuse.cached.paths.max
Fuse.ReadWriteFileCount	GAUGE	Total number of files being opened for reading or writing concurrently.
Fuse.TotalCalls	TIMER	Throughput of JNI FUSE operation calls. This metrics indicates how busy the Alluxio Fuse application is serving requests

Fuse reading/writing file count can be used as the indicators for Fuse application pressure. If a large amount of concurrent read/write occur in a short period of time, each of the read/write operations may take longer time to finish.

When a user or an application runs a filesystem command under Fuse mount point, this command will be processed and translated by operating system which will trigger the related Fuse operations exposed in AlluxioFuse. The count of how many times each operation is called, and the duration of each call will be recorded with metrics name Fuse.<FUSE_OPERATION_NAME> dynamically.

The important Fuse metrics include:

Metric Name	Description
Fuse.readdir	The duration metrics of listing a directory
Fuse.getattr	The duration metrics of getting the metadata of a file
Fuse.open	The duration metrics of opening a file for read or overwrite
Fuse.read	The duration metrics of reading a part of a file
Fuse.create	The duration metrics of creating a file for write
Fuse.write	The duration metrics of writing a file
Fuse.release	The duration metrics of closing a file after read or write. Note that release is async so fuse threads will not wait for release to finish
Fuse.mkdir	The duration metrics of creating a directory
Fuse.unlink	The duration metrics of removing a file or a directory
Fuse.rename	The duration metrics of renaming a file or a directory
Fuse.chmod	The duration metrics of modifying the mode of a file or a directory
Fuse.chown	The duration metrics of modifying the user and/or group ownership of a file or a directory

Fuse related metrics include:

• Client.TotalRPCClientsshows the total number of RPC clients exist that is using to or can be used to connect to master or worker for operations.

• Worker metrics with Direct keyword. When Fuse is embedded in worker process, it can go through worker internal API to read from / write to this worker. The related metrics are ended with Direct. For example, Worker.BytesReadDirect shows how many bytes are served by this worker to its embedded Fuse client for read.

• If alluxio.user.block.read.metrics.enabled=true is configured, Client.BlockReadChunkRemote will be recorded. This metric shows the duration statistics of reading data from remote workers via gRPC.

Client.TotalRPCClients and Fuse.TotalCalls metrics are good indicator of the current load of the Fuse applications. If applications (e.g. Tensorflow) are running on top of Alluxio Fuse but these two metrics show a much lower value than before, the training job may be stuck with Alluxio.

Process Common Metrics

The following metrics are collected on each instance (Master, Worker or Client).

JVM Attributes

Metric Name	Description
name	The name of the JVM
uptime	The uptime of the JVM
vendor	The current JVM vendor

Garbage Collector Statistics

Metric Name	Description
PS-MarkSweep.count	Total number of mark and sweep
PS-MarkSweep.time	The time used to mark and sweep
PS-Scavenge.count	Total number of scavenge
PS-Scavenge.time	The time used to scavenge

Memory Usage

Alluxio provides overall and detailed memory usage information. Detailed memory usage information of code cache, compressed class space, metaspace, PS Eden space, PS old gen, and PS survivor space is collected in each process.

A subset of the memory usage metrics are listed as following:

Metric Name	Description
total.committed	The amount of memory in bytes that is guaranteed to be available for use by the JVM
total.init	The amount of the memory in bytes that is available for use by the JVM
total.max	The maximum amount of memory in bytes that is available for use by the JVM
total.used	The amount of memory currently used in bytes
heap.committed	The amount of memory from heap area guaranteed to be available
heap.init	The amount of memory from heap area available at initialization
heap.max	The maximum amount of memory from heap area that is available
heap.usage	The amount of memory from heap area currently used in GB
heap.used	The amount of memory from heap area that has been used
pools.Code-Cache.used	Used memory of collection usage from the pool from which memory is used for compilation and storage of native code
pools.Compressed-Class-Space.used	Used memory of collection usage from the pool from which memory is use for class metadata
pools.PS-Eden-Space.used	Used memory of collection usage from the pool from which memory is initially allocated for most objects
pools.PS-Survivor-Space.used	Used memory of collection usage from the pool containing objects that have survived the garbage collection of the Eden space

ClassLoading Statistics

Metric Name	Description
loaded	The total number of classes loaded
unloaded	The total number of unloaded classes

Thread Statistics

Metric Name	Description
count	The current number of live threads
daemon.count	The current number of live daemon threads
peak.count	The peak live thread count
total_started.count	The total number of threads started
deadlock.count	The number of deadlocked threads
deadlock	The call stack of each thread related deadlock
new.count	The number of threads with new state
blocked.count	The number of threads with blocked state
runnable.count	The number of threads with runnable state
terminated.count	The number of threads with terminated state
timed_waiting.count	The number of threads with timed_waiting state