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https://issues.apache.org/jira/browse/FLINK-7873?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16268730#comment-16268730
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ASF GitHub Bot commented on FLINK-7873:
---------------------------------------

Github user sihuazhou commented on a diff in the pull request:

    https://github.com/apache/flink/pull/5074#discussion_r153493396
  
    --- Diff: 
flink-runtime/src/main/java/org/apache/flink/runtime/taskexecutor/TaskManagerServices.java
 ---
    @@ -190,6 +199,11 @@ public static TaskManagerServices fromConfiguration(
     
                final JobLeaderService jobLeaderService = new 
JobLeaderService(taskManagerLocation);
     
    +           final CheckpointCacheManager checkpointCacheManager = new 
CheckpointCacheManager(
    +                   new ScheduledThreadPoolExecutor(1),
    +                   Executors.directExecutor(),
    +                   taskManagerServicesConfiguration.getTmpDirPaths()[0]);
    --- End diff --
    
    You're right. I even thought we should add a configuration for local 
recovery to store the data.


> Introduce CheckpointCacheManager for reading checkpoint data locally when 
> performing failover
> ---------------------------------------------------------------------------------------------
>
>                 Key: FLINK-7873
>                 URL: https://issues.apache.org/jira/browse/FLINK-7873
>             Project: Flink
>          Issue Type: New Feature
>          Components: State Backends, Checkpointing
>    Affects Versions: 1.3.2
>            Reporter: Sihua Zhou
>            Assignee: Sihua Zhou
>
> Why i introduce this:
>     Current recover strategy will always read checkpoint data from remote 
> FileStream (HDFS). This will cost a lot of bandwidth when the state is so big 
> (e.g. 1T). What's worse, if this job performs recover again and again, it can 
> eat up all network bandwidth and do a huge hurt to cluster. So, I proposed 
> that we can cache the checkpoint data locally, and read checkpoint data from 
> local cache as well as we can, we read the data from remote only if we fail 
> locally. The advantage is that if a execution is assigned to the same 
> TaskManager as before, it can save a lot of bandwith, and obtain a faster 
> recover.
> Solution:
>     TaskManager do the cache job and manage the cached data itself. It simple 
> use a TTL-like method to manage cache entry's dispose, we dispose a entry if 
> it wasn't be touched for a X time, once we touch a entry we reset the TTL for 
> it. In this way, all jobs is done by TaskManager, it transparent to 
> JobManager. The only problem is that we may dispose a entry that maybe 
> useful, in this case, we have to read from remote data finally, but users can 
> avoid this by set a proper TTL value according to checkpoint interval and 
> other things.
> Can someone give me some advice? I would appreciate it very much~



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