[Gluster-users] Glusterfs performance tweaks

[Vijay Bellur]

On 04/08/2015 02:57 PM, Punit Dambiwal wrote:
> Hi,
>
> I am getting very slow throughput in the glusterfs (dead slow...even
> SATA is better) ... i am using all SSD in my environment.....
>
> I have the following setup :-
> A. 4* host machine with Centos 7(Glusterfs 3.6.2 | Distributed
> Replicated | replica=2)
> B. Each server has 24 SSD as bricks…(Without HW Raid | JBOD)
> C. Each server has 2 Additional ssd for OS…
> D. Network 2*10G with bonding…(2*E5 CPU and 64GB RAM)
>
> Note :- Performance/Throughput slower then Normal SATA 7200 RPM…even i
> am using all SSD in my ENV..
>
> Gluster Volume options :-
>
> +++++++++++++++
> Options Reconfigured:
> performance.nfs.write-behind-window-size: 1024MB
> performance.io-thread-count: 32
> performance.cache-size: 1024MB
> cluster.quorum-type: auto
> cluster.server-quorum-type: server
> diagnostics.count-fop-hits: on
> diagnostics.latency-measurement: on
> nfs.disable: on
> user.cifs: enable
> auth.allow: *
> performance.quick-read: off
> performance.read-ahead: off
> performance.io-cache: off
> performance.stat-prefetch: off
> cluster.eager-lock: enable
> network.remote-dio: enable
> storage.owner-uid: 36
> storage.owner-gid: 36
> server.allow-insecure: on
> network.ping-timeout: 0
> diagnostics.brick-log-level: INFO
> +++++++++++++++++++
>
> Test with SATA and Glusterfs SSD….
> ———————
> Dell EQL (SATA disk 7200 RPM)
> —-
> [root at mirror ~]#
> 4096+0 records in
> 4096+0 records out
> 268435456 bytes (268 MB) copied, 20.7763 s, 12.9 MB/s
> [root at mirror ~]# dd if=/dev/zero of=test bs=64k count=4k oflag=dsync
> 4096+0 records in
> 4096+0 records out
> 268435456 bytes (268 MB) copied, 23.5947 s, 11.4 MB/s
>
> GlsuterFS SSD
> —
> [root at sv-VPN1 ~]# dd if=/dev/zero of=test bs=64k count=4k oflag=dsync
> 4096+0 records in
> 4096+0 records out
> 268435456 bytes (268 MB) copied, 66.2572 s, 4.1 MB/s
> [root at sv-VPN1 ~]# dd if=/dev/zero of=test bs=64k count=4k oflag=dsync
> 4096+0 records in
> 4096+0 records out
> 268435456 bytes (268 MB) copied, 62.6922 s, 4.3 MB/s
> ————————
>
> Please let me know what i should do to improve the performance of my
> glusterfs…


What is the throughput that you get when you run these commands on the 
disks directly without gluster in the picture?

By running dd with dsync you are ensuring that there is no buffering 
anywhere in the stack and that is the reason why low throughput is being 
observed.

-Vijay

-Vijay