Job Service
Architecture Overview
The Alluxio Job Service is a task scheduling framework responsible for assigning a number of different types of operations to Job Workers.
The Master is responsible for distributing a job into smaller tasks for the Job Workers to execute and managing the status of the job’s completion.
The Job Workers queues tasks from the Job Master and manages a configurable fixed threadpool
(alluxio.job.worker.threadpool.size) to complete these tasks.
Different Types of Jobs
Load
Load Job is used as part of the fs distributedLoad CLI command and loads files to Alluxio
with specified amount of replication
Migrate
Migrate Job is used as part of the fs distributedCp and fs distributedMv CLI command and is responsible
for copying/moving with a specified WriteType.
Persist
Persist Job is used both indirectly as part of the fs persist CLI command and background
persisting when writing to Alluxio with ASYNC_THROUGH
WriteType.
The job is responsible for persisting a file in Alluxio to a particular ufs path.
Evict
Evict Job is indirectly used by fs free CLI command and replication background process.
The job is responsible for evicting a specified number of replicated blocks from Alluxio.
Move
Move Job is used by the replication background process to move blocks from one worker to another.
Replicate
Replicate job is used by the replication background process to replicate blocks from a worker to a specified number of other workers.
Data Transformation
The job service also supports data transformation. More details can be found at Data Transformations
Inspection Commands
The job service provides a number of inspection commands.
fsadmin report jobservice
fsadmin report jobservice will report a summary of the job service.
$ ./bin/alluxio fsadmin report jobservice
Worker: MigrationTest-workers-2 Task Pool Size: 10 Unfinished Tasks: 1303 Active Tasks: 10 Load Avg: 1.08, 0.64, 0.27
Worker: MigrationTest-workers-3 Task Pool Size: 10 Unfinished Tasks: 1766 Active Tasks: 10 Load Avg: 1.02, 0.48, 0.21
Worker: MigrationTest-workers-1 Task Pool Size: 10 Unfinished Tasks: 1808 Active Tasks: 10 Load Avg: 0.73, 0.5, 0.23
Status: CREATED Count: 4877
Status: CANCELED Count: 0
Status: FAILED Count: 1
Status: RUNNING Count: 0
Status: COMPLETED Count: 8124
10 Most Recently Modified Jobs:
Timestamp: 10-28-2020 22:02:34:001 Id: 1603922371976 Name: Persist Status: COMPLETED
Timestamp: 10-28-2020 22:02:34:001 Id: 1603922371982 Name: Persist Status: COMPLETED
(only a subset of the results is shown)
10 Most Recently Failed Jobs:
Timestamp: 10-24-2019 17:15:22:946 Id: 1603922372008 Name: Persist Status: FAILED
10 Longest Running Jobs:
job ls
job ls will list jobs that are running or have run on the job service.
$ ./bin/alluxio job ls
1613673433925 Persist COMPLETED
1613673433926 Persist COMPLETED
1613673433927 Persist COMPLETED
1613673433928 Persist COMPLETED
1613673433929 Persist COMPLETED
job stat -v
job stat -v <job_id> will list detailed information about a job.
(Adding -v includes information about the individual tasks on the workers)
bin/alluxio job stat -v 1613673433929
ID: 1613673433929
Name: Persist
Description: PersistConfig{filePath=/test5/lib/alluxio-underfs-cosn-2.5.0-SNAPSHOT.jar, mountId=1, overwrite=false, ufsPath=...
Status: COMPLETED
Task 0
Worker: 192.168.42.71
Status: COMPLETED