缓存预加载

分布式加载允许用户高效地将数据从 UFS 加载到 Alluxio 集群。这可用于初始化 Alluxio 集群，以便在 Alluxio 上运行工作负载时能够立即提供缓存数据。例如，分布式加载可用于为机器学习作业预取数据，从而加快训练过程。分布式加载可利用文件分割和多重复制来加强高并发数据访问场景中的文件分发。

使用方法

有两种触发分布式加载的推荐方法：

任务加载 CLI

任务加载命令可用于将数据从 UFS（底层文件系统）加载到 Alluxio 集群。 CLI 会向 Alluxio coordinator 发送加载请求，coordinator 随后会将加载操作分发到所有 worker 节点。

bin/alluxio job load [flags] <path>

# 输出示例
Progress for loading path '/path':
        Settings:       bandwidth: unlimited    verify: false
        Job State: SUCCEEDED
        Files Processed: 1000
        Bytes Loaded: 125.00MB
        Throughput: 2509.80KB/s
        Block load failure rate: 0.00%
        Files Failed: 0

有关 CLI 的详细用法，请参阅 job load 文档。

REST API

与 CLI 类似，REST API 也可用于加载数据。请求可以发送到任意 worker 节点，worker 节点会将请求转发给 Alluxio coordinator，由 coordinator 分发到所有其他 worker 节点。

通过发送 POST 请求提交作业，请求中应包含目录路径，并将 submit 作为 optType 查询参数。

curl --request POST 'http://{worker_host}:{http_port}/v1/load?path={path}&opType=submit'

请求和响应示例：

curl -v -X POST http://172.30.16.110:19999/v1/load?path=s3://test&opType=submit

# 输出示例
* About to connect() to 172.30.16.110 port 19999 (#0)
*   Trying 172.30.16.110...
* Connected to 172.30.16.110 (172.30.16.110) port 19999 (#0)
> POST /v1/load?path=s3://test&opType=submit HTTP/1.1
> User-Agent: curl/7.29.0
> Host: 172.30.16.110:19999
> Accept: */*
> Content-Length: 183
>
* upload completely sent off: 183 out of 183 bytes
< HTTP/1.1 200 OK
< Date: Wed, 10 Apr 2024 05:47:17 GMT
< Content-Length: 4
< Server: Jetty(9.4.53.v20231009)
<
* Connection #0 to host 172.30.16.110 left intact
true

可以通过发送路径相同的 GET 请求，并将 progress 作为 opType 查询参数来检查进度。

curl --request GET 'http://{worker_host}:{http_port}/v1/load?path={path}&opType=progress'

请求和响应示例：

curl -v -X GET http://host:19999/v1/load?path=s3://test&opType=progress
结果：
* About to connect() to 172.30.16.110 port 19999 (#0)
*   Trying 172.30.16.110...
* Connected to 172.30.16.110 (172.30.16.110) port 19999 (#0)
> GET /v1/load?path=s3://test&opType=progress
> User-Agent: curl/7.29.0
> Host: 172.30.16.110:19999
> Accept: */*
> Content-Length: 81
>
* upload completely sent off: 81 out of 81 bytes
< HTTP/1.1 200 OK
< Date: Wed, 10 Apr 2024 05:48:49 GMT
< Content-Length: 572
< Server: Jetty(9.4.53.v20231009)
<
* Connection #0 to host 172.30.16.110 left intact
"{\"mVerbose\":true,\"mJobState\":\"RUNNING\",\"mVerificationEnabled\":false,\"mSkippedByteCount\":0,\"mLoadedByteCount\":0,\"mScannedInodesCount\":18450,\"mLoadedNonEmptyFileCopiesCount\":0,\"mThroughput\":0,\"mFailureFilesPercentage\":0.0,\"mFailureSubTasksPercentage\":0.0,\"mRetrySubTasksPercentage\":0.0,\"mFailedFileCount\":0,\"mRecentFailedSubtasksWithReasons\":[],\"mRecentRetryingSubtasksWithReasons\":[],\"mSkipIfExists\":true,\"mMetadataOnly\":true,\"mRunningStage\":\"LOADING\",\"mRetryDeadLetterQueueSize\":0,\"mTimeElapsed\":87237,\"mSegmentEnabled\":false}"

可以通过相同路径发送 POST 请求来终止加载操作，并将 stop 作为 opType 查询参数。

curl --request POST 'http://{worker_host}:{http_port}/v1/load?path={path}&opType=stop'

请求和响应示例：

curl -v -X POST http://host:19999/v1/load?path=s3://test&opType=stop

* 结果示例：
* About to connect() to 172.30.16.110 port 19999 (#0)
*   Trying 172.30.16.110...
* Connected to 172.30.16.110 (172.30.16.110) port 19999 (#0)
> POST /v1/load?path=s3://test&opType=stop
> User-Agent: curl/7.29.0
> Host: 172.30.16.110:19999
> Accept: */*
> Content-Length: 42
>
* upload completely sent off: 42 out of 42 bytes
< HTTP/1.1 200 OK
< Date: Wed, 10 Apr 2024 05:51:56 GMT
< Content-Length: 5
< Server: Jetty(9.4.53.v20231009)
<
* Connection #0 to host 172.30.16.110 left intact
true

Last updated 5 days ago