[Gluster-users] Glusterfs performance tweaks

Fri Apr 10 15:45:34 UTC 2015

Hi Ben,

That means if i will not attach the SSD in to brick...even not install
glusterfs on the server...it gives me throughput about 300mb/s but once i
will install glusterfs and add this ssd in to glusterfs volume it gives me
16 mb/s...

On Fri, Apr 10, 2015 at 9:32 PM, Ben Turner <bturner at redhat.com> wrote:

> ----- Original Message -----
> > From: "Punit Dambiwal" <hypunit at gmail.com>
> > To: "Ben Turner" <bturner at redhat.com>
> > Cc: "Vijay Bellur" <vbellur at redhat.com>, gluster-users at gluster.org
> > Sent: Thursday, April 9, 2015 9:36:59 PM
> > Subject: Re: [Gluster-users] Glusterfs performance tweaks
> >
> > Hi Ben,
> >
> > But without glusterfs if i run the same command with dsync on the same
> > ssd...it gives me good throughput...all setup (CPU,RAM,Network are same)
> > the only difference is no glusterfs...
> >
> > [root at cpu09 mnt]# 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, 0.935646 s, 287 MB/s
> > [root at cpu09 mnt]#
> >
> > [image: Inline image 1]
> >
> > But on the top of the glusterfs it gives too slow performance....i run
> the
> > ssd trim every night to clean the garbage collection...i think there is
> > something need to do from gluster or OS side to improve the
> > performance....otherwise no use to use the ALL SSD with gluster because
> > with all SSD you will get the performance slower then SATA....
> >
> >
> >
> > On Fri, Apr 10, 2015 at 2:12 AM, Ben Turner <bturner at redhat.com> wrote:
> >
> > > ----- Original Message -----
> > > > From: "Punit Dambiwal" <hypunit at gmail.com>
> > > > To: "Vijay Bellur" <vbellur at redhat.com>
> > > > Cc: gluster-users at gluster.org
> > > > Sent: Wednesday, April 8, 2015 9:55:38 PM
> > > > Subject: Re: [Gluster-users] Glusterfs performance tweaks
> > > >
> > > > Hi Vijay,
> > > >
> > > > If i run the same command directly on the brick...
>
> What does this mean then?  Running directly on the brick to me means
> running directly on the SSD.  The command below is the same thing as above,
> what changed?
>
> -b
>
> > > >
> > > > [root at cpu01 1]# 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, 16.8022 s, 16.0 MB/s
> > > > [root at cpu01 1]# pwd
> > > > /bricks/1
> > > > [root at cpu01 1]#
> > > >
> > >
> > > This is your problem.  Gluster is only as fast as its slowest piece,
> and
> > > here your storage is the bottleneck.  Being that you get 16 MB to the
> brick
> > > and 12 to gluster that works out to about 25% overhead which is what I
> > > would expect with a single thread, single brick, single client
> scenario.
> > > This may have something to do with the way SSDs write?  On my SSD at my
> > > desk I only get 11.4 MB / sec when I run that DD command:
> > >
> > > # 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, 23.065 s, 11.4 MB/s
> > >
> > > My thought is that maybe using dsync is forcing the SSD to clean the
> data
> > > or something else before writing to it:
> > >
> > > http://www.blog.solidstatediskshop.com/2012/how-does-an-ssd-write/
> > >
> > > Do your drives support fstrim?  It may be worth it to trim before you
> run
> > > and see what results you get.  Other than tuning the SSD / OS to
> perform
> > > better on the back end there isn't much we can do from the gluster
> > > perspective on that specific DD w/ the dsync flag.
> > >
> > > -b
> > >
> > > >
> > > > On Wed, Apr 8, 2015 at 6:44 PM, Vijay Bellur < vbellur at redhat.com >
> > > wrote:
> > > >
> > > >
> > > >
> > > > 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
> > > >
> > > >
> > > >
> > > > _______________________________________________
> > > > Gluster-users mailing list
> > > > Gluster-users at gluster.org
> > > > http://www.gluster.org/mailman/listinfo/gluster-users
> > >
> >
>
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