[
https://issues.apache.org/jira/browse/HDFS-6093?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13935858#comment-13935858
]
Arpit Agarwal commented on HDFS-6093:
-------------------------------------
Thanks Andrew/Colin, the values did converge!
wrt the patch:
# In addition to reducing the timeout as you suggested, can we add some
explanation to the command output, or update CentralizedCacheManagement.html in
the docs? Additionally does it make sense to display the pending
caching/uncaching counts in the output of 'dfsadmin -report'? This would make
it clear right away that there are some pending cache operations.
# {{CacheReplicationMonitor#rescan}} resets the counters to zero outside the
write lock. It should be moved inside the lock else readers might see blips
with the counters intermittently going to zero.
# Was {{stillPendingUncached}} introduced to fix a bug?
Minor code style comment: {{getPendingCachingCount}} can be condensed to
{code}
return (monitor != null ? monitor.getPendingCachingCount() : 0);
{code}
Same with {{getPendingUncachingCount}}.
Change looks good otherwise.
> Expose more caching information for debugging by users
> ------------------------------------------------------
>
> Key: HDFS-6093
> URL: https://issues.apache.org/jira/browse/HDFS-6093
> Project: Hadoop HDFS
> Issue Type: Improvement
> Components: caching
> Affects Versions: 2.4.0
> Reporter: Andrew Wang
> Assignee: Andrew Wang
> Attachments: hdfs-6093-1.patch
>
>
> When users submit a new cache directive, it's unclear if the NN has
> recognized it and is actively trying to cache it, or if it's hung for some
> other reason. It'd be nice to expose a "pending caching/uncaching" count the
> same way we expose pending replication work.
> It'd also be nice to display the aggregate cache capacity and usage in
> dfsadmin -report, since we already have have it as a metric and expose it
> per-DN in report output.
--
This message was sent by Atlassian JIRA
(v6.2#6252)
