[ovirt-users] [Gluster-users] Very poor GlusterFS performance

Krutika Dhananjay kdhananj at redhat.com
Wed Jun 21 10:32:34 UTC 2017


No. It's just that in the internal testing that was done here, increasing
the thread count beyond 4 did not improve the performance any further.

-Krutika

On Tue, Jun 20, 2017 at 11:30 PM, mabi <mabi at protonmail.ch> wrote:

> Dear Krutika,
>
> Sorry for asking so naively but can you tell me on what factor do you base
> that the client and server event-threads parameters for a volume should be
> set to 4?
>
> Is this metric for example based on the number of cores a GlusterFS server
> has?
>
> I am asking because I saw my GlusterFS volumes are set to 2 and would like
> to set these parameters to something meaningful for performance tuning. My
> setup is a two node replica with GlusterFS 3.8.11.
>
> Best regards,
> M.
>
>
>
> -------- Original Message --------
> Subject: Re: [Gluster-users] [ovirt-users] Very poor GlusterFS performance
> Local Time: June 20, 2017 12:23 PM
> UTC Time: June 20, 2017 10:23 AM
> From: kdhananj at redhat.com
> To: Lindsay Mathieson <lindsay.mathieson at gmail.com>
> gluster-users <gluster-users at gluster.org>, oVirt users <users at ovirt.org>
>
> Couple of things:
> 1. Like Darrell suggested, you should enable stat-prefetch and increase
> client and server event threads to 4.
> # gluster volume set <VOL> performance.stat-prefetch on
> # gluster volume set <VOL> client.event-threads 4
> # gluster volume set <VOL> server.event-threads 4
>
> 2. Also glusterfs-3.10.1 and above has a shard performance bug fix -
> https://review.gluster.org/#/c/16966/
>
> With these two changes, we saw great improvement in performance in our
> internal testing.
>
> Do you mind trying these two options above?
> -Krutika
>
> On Tue, Jun 20, 2017 at 1:00 PM, Lindsay Mathieson <
> lindsay.mathieson at gmail.com> wrote:
>
>> Have you tried with:
>>
>> performance.strict-o-direct : off
>> performance.strict-write-ordering : off
>> They can be changed dynamically.
>>
>>
>> On 20 June 2017 at 17:21, Sahina Bose <sabose at redhat.com> wrote:
>>
>>> [Adding gluster-users]
>>>
>>> On Mon, Jun 19, 2017 at 8:16 PM, Chris Boot <bootc at bootc.net> wrote:
>>>
>>>> Hi folks,
>>>>
>>>> I have 3x servers in a "hyper-converged" oVirt 4.1.2 + GlusterFS 3.10
>>>> configuration. My VMs run off a replica 3 arbiter 1 volume comprised of
>>>> 6 bricks, which themselves live on two SSDs in each of the servers (one
>>>> brick per SSD). The bricks are XFS on LVM thin volumes straight onto the
>>>> SSDs. Connectivity is 10G Ethernet.
>>>>
>>>> Performance within the VMs is pretty terrible. I experience very low
>>>> throughput and random IO is really bad: it feels like a latency issue.
>>>> On my oVirt nodes the SSDs are not generally very busy. The 10G network
>>>> seems to run without errors (iperf3 gives bandwidth measurements of >=
>>>> 9.20 Gbits/sec between the three servers).
>>>>
>>>> To put this into perspective: I was getting better behaviour from NFS4
>>>> on a gigabit connection than I am with GlusterFS on 10G: that doesn't
>>>> feel right at all.
>>>>
>>>> My volume configuration looks like this:
>>>>
>>>> Volume Name: vmssd
>>>> Type: Distributed-Replicate
>>>> Volume ID: d5a5ddd1-a140-4e0d-b514-701cfe464853
>>>> Status: Started
>>>> Snapshot Count: 0
>>>> Number of Bricks: 2 x (2 + 1) = 6
>>>> Transport-type: tcp
>>>> Bricks:
>>>> Brick1: ovirt3:/gluster/ssd0_vmssd/brick
>>>> Brick2: ovirt1:/gluster/ssd0_vmssd/brick
>>>> Brick3: ovirt2:/gluster/ssd0_vmssd/brick (arbiter)
>>>> Brick4: ovirt3:/gluster/ssd1_vmssd/brick
>>>> Brick5: ovirt1:/gluster/ssd1_vmssd/brick
>>>> Brick6: ovirt2:/gluster/ssd1_vmssd/brick (arbiter)
>>>> Options Reconfigured:
>>>> nfs.disable: on
>>>> transport.address-family: inet6
>>>> performance.quick-read: off
>>>> performance.read-ahead: off
>>>> performance.io-cache: off
>>>> performance.stat-prefetch: off
>>>> performance.low-prio-threads: 32
>>>> network.remote-dio: off
>>>> cluster.eager-lock: enable
>>>> cluster.quorum-type: auto
>>>> cluster.server-quorum-type: server
>>>> cluster.data-self-heal-algorithm: full
>>>> cluster.locking-scheme: granular
>>>> cluster.shd-max-threads: 8
>>>> cluster.shd-wait-qlength: 10000
>>>> features.shard: on
>>>> user.cifs: off
>>>> storage.owner-uid: 36
>>>> storage.owner-gid: 36
>>>> features.shard-block-size: 128MB
>>>> performance.strict-o-direct: on
>>>> network.ping-timeout: 30
>>>> cluster.granular-entry-heal: enable
>>>>
>>>> I would really appreciate some guidance on this to try to improve things
>>>> because at this rate I will need to reconsider using GlusterFS
>>>> altogether.
>>>>
>>>
>>> Could you provide the gluster volume profile output while you're running
>>> your I/O tests.
>>> # gluster volume profile <volname> start
>>> to start profiling
>>> # gluster volume profile <volname> info
>>> for the profile output.
>>>
>>>
>>>>
>>>> Cheers,
>>>> Chris
>>>>
>>>> --
>>>> Chris Boot
>>>> bootc at bootc.net
>>>> _______________________________________________
>>>> Users mailing list
>>>> Users at ovirt.org
>>>> http://lists.ovirt.org/mailman/listinfo/users
>>>>
>>>
>>>
>>> _______________________________________________
>>> Gluster-users mailing list
>>> Gluster-users at gluster.org
>>> http://lists.gluster.org/mailman/listinfo/gluster-users
>>>
>>
>>
>>
>> --
>> Lindsay
>>
>> _______________________________________________
>> Users mailing list
>> Users at ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/users
>>
>>
>
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