Bug 1250809

Summary:	Enable multi-threaded epoll for glusterd process
Product:	[Community] GlusterFS	Reporter:	krishnan parthasarathi <kparthas>
Component:	glusterd	Assignee:	krishnan parthasarathi <kparthas>
Status:	CLOSED CURRENTRELEASE	QA Contact:
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	3.7.0	CC:	bugs, gluster-bugs, nsathyan
Target Milestone:	---
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	glusterfs-3.7.4	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:	1242421	Environment:
Last Closed:	2015-09-09 09:39:07 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:
Embargoed:
Bug Depends On:	1242421
Bug Blocks:	1241336

Description krishnan parthasarathi 2015-08-06 04:36:10 UTC

+++ This bug was initially created as a clone of Bug #1242421 +++

Description of problem:

glusterd uses single epoll worker thread for sending/receiving notifications. gluster commands which communicate with many daemons, e.g snapshot-create could take longer than ping-timeout secs on a volume with large no. of snapshots times out. With introduction of multi-threaded epoll support in glusterd, we could add more epoll workers to (reduce latency and) avoid spurious disconnects due to ping-timeout.

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1.
2.
3.

Actual results:


Expected results:


Additional info:

--- Additional comment from Anand Avati on 2015-07-13 06:04:35 EDT ---

REVIEW: http://review.gluster.org/11630 (glusterd: use 2 epoll worker threads by default) posted (#2) for review on master by Krishnan Parthasarathi (kparthas)

Comment 1 Anand Avati 2015-08-24 03:45:06 UTC

REVIEW: http://review.gluster.org/11991 (event: add dispatched flag to know if event_dispatch was called) posted (#2) for review on release-3.7 by Krishnan Parthasarathi (kparthas)

Comment 2 krishnan parthasarathi 2015-08-24 08:32:43 UTC

http://review.gluster.org/11630 introduced multi-threaded epoll for glusterd on Linux systems. This patch creates incorrect no. of worker threads than the default. This is because, multi-threaded epoll subsystem doesn't allow reconfiguring of no. of threads before event_dispatch is called. Fix in comment#1 fixes that.

tl;dr
With http://review.gluster.org/11630 and http://review.gluster.org/11991 glusterd is capable of listening for epoll(7) events from 2 threads by default.

Comment 3 krishnan parthasarathi 2015-08-28 11:04:08 UTC

http://review.gluster.org/11991 doesn't fix the problem mentioned in comment#2. It has been abandoned in favour of http://review.gluster.org/12004.

Comment 4 Kaushal 2015-09-09 09:39:07 UTC

This bug is getting closed because a release has been made available that should address the reported issue. In case the problem is still not fixed with glusterfs-3.7.4, please open a new bug report.

glusterfs-3.7.4 has been announced on the Gluster mailinglists [1], packages for several distributions should become available in the near future. Keep an eye on the Gluster Users mailinglist [2] and the update infrastructure for your distribution.

[1] http://thread.gmane.org/gmane.comp.file-systems.gluster.devel/12496
[2] http://thread.gmane.org/gmane.comp.file-systems.gluster.user