[
https://issues.apache.org/jira/browse/HDFS-14401?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16830376#comment-16830376
]
Rakesh R commented on HDFS-14401:
---------------------------------
Overall the patch looks good and I think its nearing completion. Could you
please take care below comments:
# Rename PmemVolumeManager variable '{{i}}' to '{{nextIndex}}'.
# How about resetting {{nextIndex}} to avoid growing to infinity, probably can
refer below idea or you can explicitly reset {{nextIndex=0}}, {{if (nextIndex
== count)}}.
{code:java}
private byte nextIndex = 0;
..
..
while (k++ != count) {
nextIndex = (byte) (nextIndex % count);
byte index = nextIndex;
nextIndex++;
long availableBytes = usedBytesCounts.get(index).getAvailableBytes();
if (availableBytes >= bytesCount) {
return index;
}
if (availableBytes > maxAvailableSpace) {
maxAvailableSpace = availableBytes;
}
}
{code}
# Instead of {{memCacheStats.getCacheUsed()}}, it should be
{{cacheLoader.getCacheUsed()}}, right?
{code:java}
LOG.debug("Caching of {} was aborted. We are now caching only {} "
+ "bytes in total.", key, cacheLoader.getCacheUsed());
{code}
# Please double check the chances of any scenario where it adds
{{blockKeyToVolume.put(key, index);}} entry and then
{{usedBytesCounts.get(index).reserve(bytesCount);}} return -1?
> Refine the implementation for HDFS cache on SCM
> -----------------------------------------------
>
> Key: HDFS-14401
> URL: https://issues.apache.org/jira/browse/HDFS-14401
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Components: caching, datanode
> Reporter: Feilong He
> Assignee: Feilong He
> Priority: Major
> Attachments: HDFS-14401.000.patch, HDFS-14401.001.patch,
> HDFS-14401.002.patch, HDFS-14401.003.patch, HDFS-14401.004.patch,
> HDFS-14401.005.patch, HDFS-14401.006.patch
>
>
> In this Jira, we will refine the implementation for HDFS cache on SCM, such
> as: 1) Handle full pmem volume in VolumeManager; 2) Refine pmem volume
> selection impl; 3) Clean up MapppableBlockLoader interface; etc.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
