You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@hbase.apache.org by "Lars Hofhansl (JIRA)" <ji...@apache.org> on 2014/07/27 21:39:39 UTC

[jira] [Comment Edited] (HBASE-11360) SnapshotFileCache refresh logic based on modified directory time might be insufficient

    [ https://issues.apache.org/jira/browse/HBASE-11360?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14075724#comment-14075724 ] 

Lars Hofhansl edited comment on HBASE-11360 at 7/27/14 7:39 PM:
----------------------------------------------------------------

Actually, after HBASE-7987 this is no longer a problem anyway. Snapshots will no longer have 1000's of files for large table but only a manifest.

So the options are:
# commit this to 0.94, 0.96, 0.98 and have them be vastly different from trunk in this respect
# backport HBASE-7987 to 0.94, 0.96, and 0.98
# do nothing. The problem will be fixed in 1.0

#2 is probably too big/risky in 0.94. We'd also need the old code around anyway.
So let's just do #1?

Comments?


was (Author: lhofhansl):
Actually, after HBASE-7987 this is no longer a problem anyway. Snapshots will no longer have 1000's of files for large table but only a manifest.

So the options are:
# commit this to 0.94, 0.96, 0.98 and have them be vastly different in this respect
# backport HBASE-7987 to 0.94, 0.96, and 0.98
# do nothing. The problem will be fixed in 1.0

#2 is probably too big/risky in 0.94. We'd also need the old code around anyway.
So let's just do #1?

Comments?

> SnapshotFileCache refresh logic based on modified directory time might be insufficient
> --------------------------------------------------------------------------------------
>
>                 Key: HBASE-11360
>                 URL: https://issues.apache.org/jira/browse/HBASE-11360
>             Project: HBase
>          Issue Type: Bug
>    Affects Versions: 0.94.19
>            Reporter: churro morales
>             Fix For: 0.99.0, 0.98.5, 0.94.22
>
>         Attachments: 11360-0.98.txt, HBASE-11360-0.94.patch, HBASE-11360-0.96.patch
>
>
> Right now we decide whether to refresh the cache based on the lastModified timestamp of all the snapshots and those "running" snapshots which is located in the /hbase/.hbase-snapshot/.tmp/<snapshot> directory
> We ran a ExportSnapshot job which takes around 7 minutes between creating the directory and copying all the files. 
> Thus the modified time for the 
> /hbase/.hbase-snapshot/.tmp directory was 7 minutes earlier than the modified time of the
> /hbase/.hbase-snapshot/.tmp/<snapshot> directory
> Thus the cache refresh happens and doesn't pick up all the files but thinks its up to date as the modified time of the .tmp directory never changes.
> This is a bug as when the export job starts the cache never contains the files for the "running" snapshot and will fail.



--
This message was sent by Atlassian JIRA
(v6.2#6252)