Bug 1385468

Summary: During rebalance continuous "table not found" warning messages are seen in rebalance logs
Product: Red Hat Gluster Storage Reporter: Prasad Desala <tdesala>
Component: md-cacheAssignee: Poornima G <pgurusid>
Status: CLOSED ERRATA QA Contact: Prasad Desala <tdesala>
Severity: high Docs Contact:
Priority: unspecified    
Version: rhgs-3.2CC: amukherj, anraj, kramdoss, nbalacha, pgurusid, rhinduja, rhs-bugs, rjoseph, storage-qa-internal
Target Milestone: ---   
Target Release: RHGS 3.2.0   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: glusterfs-3.8.4-3 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2017-03-23 06:10:34 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On:    
Bug Blocks: 1351528    

Description Prasad Desala 2016-10-17 06:38:27 UTC
Description of problem:
=======================
During rebalance continuous "table not found" warning messages are seen in rebalance logs. Also, no files were rebalanced and rebalance completed with failures.
 
Version-Release number of selected component (if applicable):
3.8.4-2.26.git0a405a4.el7rhgs.x86_64

How reproducible:
1/1

Steps to Reproduce:
===================
1) Create a distributed replica volume and start it.
2) Enable md-cache required settings on the volume ( Please see gluster volume info output for enabled md-cache settings)
3) Fuse mount the volume on multiple clients.
4) Perform below tasks simultaneosuly from multiple clients,
     a) From client-1, touch -->  for i in {1..20000};do touch f$i;done
	 b) From client-2, create hardlinks for the created files , for i in {1..20000};do ln f$i fl$i;done
	 c) From client-3, change the permissions for the created files, for i in {1..20000};do ln f$i fl$i;done
	 d) From client-4, do a continuous lookup.
5) While the tasks in step-4 are in progress, add few bricks to the volume and start rebalance.
Wait till step-4 and step-5 completes.

Actual results:
==============
During rebalance continuous "table not found" warning messages are seen in rebalance logs. Also, no files were rebalanced and rebalance completed with failures.

Expected results:
=================
There should not be any "table not found" warning messages in the rebalance logs and rebalancing files should happen without any failures/issues.

Comment 3 Prasad Desala 2016-10-17 10:50:38 UTC
In Description -> Steps to reproduce -> 4-> c, command that was used for changing the file permission is 
for i in {1..20000};do chmod 660 f$i;done

glusterfs version: 3.8.4-2.el7.x86_64
Repeated the same steps on an another setup without md-cache. During rebalance, I didn't see any "table not found" warning messages in rebalance logs but no files were rebalanced and rebalance completed with failures.

Comment 4 Poornima G 2016-10-19 05:35:37 UTC
RCA:

The upcall notification is sent to the Rebalance process as well, hence these log messages.

Fix:
Rebalance process doesn't load md-cache hence we do not need upcall to be sent to these processes. One way is to exclude the rebalance client from sending notifications to. Will discuss this with the upcall and rebalance maintainers and arrive at a conclusion.

Comment 7 Prasad Desala 2016-10-25 06:03:42 UTC
Executed few rebalance tests with 3.8.4-2.el7.x86_64 and we are not seeing these "table not found" warning messages. We are seeing this issue only with the build loaded with md-cache.

Comment 9 Poornima G 2016-11-07 13:22:25 UTC
The log messages are fixed, it should be part of the build provided on 7/9/2016. Putting it ON_QA

Comment 12 Poornima G 2016-11-08 11:06:52 UTC
Upstream patch 
http://review.gluster.org/#/c/15398/
Downstream patch 
https://code.engineering.redhat.com/gerrit/#/c/87047/

It is fixed in version 3.8.4-3

Comment 15 Prasad Desala 2016-11-23 07:39:43 UTC
Verified the fix against glusterfs version: 3.8.4-5.el7rhgs.x86_64.

"table not found" warnings messages are not seen in rebalance logs during rebalance. Hence, moving this BZ to Verified.

Comment 17 errata-xmlrpc 2017-03-23 06:10:34 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHSA-2017-0486.html