[Gluster-users] Extremely slow cluster performance

Patrick Rennie patrickmrennie at gmail.com
Sat Apr 20 13:22:13 UTC 2019


Hello Gluster Users,

I am hoping someone can help me with resolving an ongoing issue I've been
having, I'm new to mailing lists so forgive me if I have gotten anything
wrong. We have noticed our performance deteriorating over the last few
weeks, easily measured by trying to do an ls on one of our top-level
folders, and timing it, which usually would take 2-5 seconds, and now takes
up to 20 minutes, which obviously renders our cluster basically unusable.
This has been intermittent in the past but is now almost constant and I am
not sure how to work out the exact cause. We have noticed some errors in
the brick logs, and have noticed that if we kill the right brick process,
performance instantly returns back to normal, this is not always the same
brick, but it indicates to me something in the brick processes or
background tasks may be causing extreme latency. Due to this ability to fix
it by killing the right brick process off, I think it's a specific file, or
folder, or operation which may be hanging and causing the increased
latency, but I am not sure how to work it out. One last thing to add is
that our bricks are getting quite full (~95% full), we are trying to
migrate data off to new storage but that is going slowly, not helped by
this issue. I am currently trying to run a full heal as there appear to be
many files needing healing, and I have all brick processes running so they
have an opportunity to heal, but this means performance is very poor. It
currently takes over 15-20 minutes to do an ls of one of our top-level
folders, which just contains 60-80 other folders, this should take 2-5
seconds. This is all being checked by FUSE mount locally on the storage
node itself, but it is the same for other clients and VMs accessing the
cluster. Initially, it seemed our NFS mounts were not affected and operated
at normal speed, but testing over the last day has shown that our NFS
clients are also extremely slow, so it doesn't seem specific to FUSE as I
first thought it might be.

I am not sure how to proceed from here, I am fairly new to gluster having
inherited this setup from my predecessor and trying to keep it going. I
have included some info below to try and help with diagnosis, please let me
know if any further info would be helpful. I would really appreciate any
advice on what I could try to work out the cause. Thank you in advance for
reading this, and any suggestions you might be able to offer.

- Patrick

This is an example of the main error I see in our brick logs, there have
been others, I can post them when I see them again too:
[2019-04-20 04:54:43.055680] E [MSGID: 113001]
[posix.c:4940:posix_getxattr] 0-gvAA01-posix: getxattr failed on
/brick1/<filename> library: system.posix_acl_default  [Operation not
supported]
[2019-04-20 05:01:29.476313] W [posix.c:4929:posix_getxattr]
0-gvAA01-posix: Extended attributes not supported (try remounting brick
with 'user_xattr' flag)

Our setup consists of 2 storage nodes and an arbiter node. I have noticed
our nodes are on slightly different versions, I'm not sure if this could be
an issue. We have 9 bricks on each node, made up of ZFS RAIDZ2 pools -
total capacity is around 560TB.
We have bonded 10gbps NICS on each node, and I have tested bandwidth with
iperf and found that it's what would be expected from this config.
Individual brick performance seems ok, I've tested several bricks using dd
and can write a 10GB files at 1.7GB/s.

# dd if=/dev/zero of=/brick1/test/test.file bs=1M count=10000
10000+0 records in
10000+0 records out
10485760000 bytes (10 GB, 9.8 GiB) copied, 6.20303 s, 1.7 GB/s

Node 1:
# glusterfs --version
glusterfs 3.12.15

Node 2:
# glusterfs --version
glusterfs 3.12.14

Arbiter:
# glusterfs --version
glusterfs 3.12.14

Here is our gluster volume status:

# gluster volume status
Status of volume: gvAA01
Gluster process                             TCP Port  RDMA Port  Online  Pid
------------------------------------------------------------------------------
Brick 01-B:/brick1/gvAA01/brick    49152     0          Y       7219
Brick 02-B:/brick1/gvAA01/brick    49152     0          Y       21845
Brick 00-A:/arbiterAA01/gvAA01/bri
ck1                                         49152     0          Y
 6931
Brick 01-B:/brick2/gvAA01/brick    49153     0          Y       7239
Brick 02-B:/brick2/gvAA01/brick    49153     0          Y       9916
Brick 00-A:/arbiterAA01/gvAA01/bri
ck2                                         49153     0          Y
 6939
Brick 01-B:/brick3/gvAA01/brick    49154     0          Y       7235
Brick 02-B:/brick3/gvAA01/brick    49154     0          Y       21858
Brick 00-A:/arbiterAA01/gvAA01/bri
ck3                                         49154     0          Y
 6947
Brick 01-B:/brick4/gvAA01/brick    49155     0          Y       31840
Brick 02-B:/brick4/gvAA01/brick    49155     0          Y       9933
Brick 00-A:/arbiterAA01/gvAA01/bri
ck4                                         49155     0          Y
 6956
Brick 01-B:/brick5/gvAA01/brick    49156     0          Y       7233
Brick 02-B:/brick5/gvAA01/brick    49156     0          Y       9942
Brick 00-A:/arbiterAA01/gvAA01/bri
ck5                                         49156     0          Y
 6964
Brick 01-B:/brick6/gvAA01/brick    49157     0          Y       7234
Brick 02-B:/brick6/gvAA01/brick    49157     0          Y       9952
Brick 00-A:/arbiterAA01/gvAA01/bri
ck6                                         49157     0          Y
 6974
Brick 01-B:/brick7/gvAA01/brick    49158     0          Y       7248
Brick 02-B:/brick7/gvAA01/brick    49158     0          Y       9960
Brick 00-A:/arbiterAA01/gvAA01/bri
ck7                                         49158     0          Y
 6984
Brick 01-B:/brick8/gvAA01/brick    49159     0          Y       7253
Brick 02-B:/brick8/gvAA01/brick    49159     0          Y       9970
Brick 00-A:/arbiterAA01/gvAA01/bri
ck8                                         49159     0          Y
 6993
Brick 01-B:/brick9/gvAA01/brick    49160     0          Y       7245
Brick 02-B:/brick9/gvAA01/brick    49160     0          Y       9984
Brick 00-A:/arbiterAA01/gvAA01/bri
ck9                                         49160     0          Y
 7001
NFS Server on localhost                     2049      0          Y
 17276
Self-heal Daemon on localhost               N/A       N/A        Y
 25245
NFS Server on 02-B                 2049      0          Y       9089
Self-heal Daemon on 02-B           N/A       N/A        Y       17838
NFS Server on 00-a                 2049      0          Y       15660
Self-heal Daemon on 00-a           N/A       N/A        Y       16218

Task Status of Volume gvAA01
------------------------------------------------------------------------------
There are no active volume tasks

And gluster volume info:

# gluster volume info

Volume Name: gvAA01
Type: Distributed-Replicate
Volume ID: ca4ece2c-13fe-414b-856c-2878196d6118
Status: Started
Snapshot Count: 0
Number of Bricks: 9 x (2 + 1) = 27
Transport-type: tcp
Bricks:
Brick1: 01-B:/brick1/gvAA01/brick
Brick2: 02-B:/brick1/gvAA01/brick
Brick3: 00-A:/arbiterAA01/gvAA01/brick1 (arbiter)
Brick4: 01-B:/brick2/gvAA01/brick
Brick5: 02-B:/brick2/gvAA01/brick
Brick6: 00-A:/arbiterAA01/gvAA01/brick2 (arbiter)
Brick7: 01-B:/brick3/gvAA01/brick
Brick8: 02-B:/brick3/gvAA01/brick
Brick9: 00-A:/arbiterAA01/gvAA01/brick3 (arbiter)
Brick10: 01-B:/brick4/gvAA01/brick
Brick11: 02-B:/brick4/gvAA01/brick
Brick12: 00-A:/arbiterAA01/gvAA01/brick4 (arbiter)
Brick13: 01-B:/brick5/gvAA01/brick
Brick14: 02-B:/brick5/gvAA01/brick
Brick15: 00-A:/arbiterAA01/gvAA01/brick5 (arbiter)
Brick16: 01-B:/brick6/gvAA01/brick
Brick17: 02-B:/brick6/gvAA01/brick
Brick18: 00-A:/arbiterAA01/gvAA01/brick6 (arbiter)
Brick19: 01-B:/brick7/gvAA01/brick
Brick20: 02-B:/brick7/gvAA01/brick
Brick21: 00-A:/arbiterAA01/gvAA01/brick7 (arbiter)
Brick22: 01-B:/brick8/gvAA01/brick
Brick23: 02-B:/brick8/gvAA01/brick
Brick24: 00-A:/arbiterAA01/gvAA01/brick8 (arbiter)
Brick25: 01-B:/brick9/gvAA01/brick
Brick26: 02-B:/brick9/gvAA01/brick
Brick27: 00-A:/arbiterAA01/gvAA01/brick9 (arbiter)
Options Reconfigured:
cluster.shd-max-threads: 4
performance.least-prio-threads: 16
cluster.readdir-optimize: on
performance.quick-read: off
performance.stat-prefetch: off
cluster.data-self-heal: on
cluster.lookup-unhashed: auto
cluster.lookup-optimize: on
cluster.favorite-child-policy: mtime
server.allow-insecure: on
transport.address-family: inet
client.bind-insecure: on
cluster.entry-self-heal: off
cluster.metadata-self-heal: off
performance.md-cache-timeout: 600
cluster.self-heal-daemon: enable
performance.readdir-ahead: on
diagnostics.brick-log-level: INFO
nfs.disable: off

Thank you for any assistance.

- Patrick
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.gluster.org/pipermail/gluster-users/attachments/20190420/49ac3425/attachment.html>


More information about the Gluster-users mailing list