Bug 1506513

On a brick multiplexing 3 node cluster setup, having 12 1 X 3 volumes and restarting all the gluster processes leaves up with some of brick status showing offline.

Steps to Reproduce:
1.brick mux enabled, max brick per process set to 3
2.had about 12 volumes,about 10 were 1x3 and 2 were 2x2 =>in total 17 bricks per node
3.did a pkill glusterfsd, glusterfs and service glusterd stop
4. did service glusterd start


Actual results:
==============
found about 11-18(different tries, different numbers) glusterfsd running, while only 7 are supposed to be created

also volume status shows bricks as offline for some of them

however, no IO impact


We would hit this in upgrade path

REVIEW: https://review.gluster.org/18577 (glusterd: fix brick restart parallelism) posted (#1) for review on master by Atin Mukherjee (amukherj)

REVIEW: https://review.gluster.org/18577 (glusterd: fix brick restart parallelism) posted (#2) for review on master by Atin Mukherjee (amukherj)

REVIEW: https://review.gluster.org/18577 (glusterd: fix brick restart parallelism) posted (#3) for review on master by Atin Mukherjee (amukherj)

COMMIT: https://review.gluster.org/18577 committed in master by  

------------- glusterd: fix brick restart parallelism

glusterd's brick restart logic is not always sequential as there is
atleast three different ways how the bricks are restarted.
1. through friend-sm and glusterd_spawn_daemons ()
2. through friend-sm and handling volume quorum action
3. through friend handshaking when there is a mimatch on quorum on
friend import.

In a brick multiplexing setup, glusterd ended up trying to spawn the
same brick process couple of times as almost in fraction of milliseconds
two threads hit glusterd_brick_start () because of which glusterd didn't
have any choice of rejecting any one of them as for both the case brick
start criteria met.

As a solution, it'd be better to control this madness by two different
flags, one is a boolean called start_triggered which indicates a brick
start has been triggered and it continues to be true till a brick dies
or killed, the second is a mutex lock to ensure for a particular brick
we don't end up getting into glusterd_brick_start () more than once at
same point of time.

Change-Id: I292f1e58d6971e111725e1baea1fe98b890b43e2
BUG: 1506513
Signed-off-by: Atin Mukherjee <amukherj>

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-3.13.0, please open a new bug report.

glusterfs-3.13.0 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://lists.gluster.org/pipermail/announce/2017-December/000087.html
[2] https://www.gluster.org/pipermail/gluster-users/