Hi Krutika,
I already have a preallocated disk on VM. Below are the current settings:
Volume Name: vms
Type: Replicate
Volume ID: 4513340d-7919-498b-bfe0-d836b5cea40b
Status: Started
Snapshot Count: 0
Number of Bricks: 1 x (2 + 1) = 3
Transport-type: tcp
Bricks:
Brick1: gluster0:/gluster/vms/brick
Brick2: gluster1:/gluster/vms/brick
Brick3: gluster2:/gluster/vms/brick (arbiter)
Options Reconfigured:
server.event-threads: 4
client.event-threads: 4
performance.client-io-threads: on
features.shard-block-size: 512MB
cluster.granular-entry-heal: enable
performance.strict-o-direct: on
network.ping-timeout: 30
storage.owner-gid: 36
storage.owner-uid: 36
user.cifs: off
features.shard: on
cluster.shd-wait-qlength: 10000
cluster.shd-max-threads: 8
cluster.locking-scheme: granular
cluster.data-self-heal-algorithm: full
cluster.server-quorum-type: server
cluster.quorum-type: auto
cluster.eager-lock: enable
network.remote-dio: off
performance.low-prio-threads: 32
performance.stat-prefetch: on
performance.io-cache: off
performance.read-ahead: off
performance.quick-read: off
transport.address-family: inet
performance.readdir-ahead: on
nfs.disable: on
nfs.export-volumes: on
Any other things one can do?
On Tue, Sep 5, 2017 at 5:57 AM, Krutika Dhananjay <kdhananj@xxxxxxxxxx> wrote:
-KrutikaSecond, I'm assuming you're using the default shard block size of 4MB (you can confirm this using `gluster volume get <VOL> shard-block-size`). In our tests, we've found that larger shard sizes perform better. So maybe change the shard-block-size to 64MB (`gluster volume set <VOL> shard-block-size 64MB`).This will at least eliminate the need for shard to perform multiple steps as part of the writes - such as creating the shard and then writing to it and then updating the aggregated file size - all of which require one network call each, which further get blown up once they reach AFR (replicate) into many more network calls.I'm assuming you are using this volume to store vm images, because I see shard in the options list.Speaking from shard translator's POV, one thing you can do to improve performance is to use preallocated images.Third, keep stat-prefetch enabled. We've found that qemu sends quite a lot of [f]stats which can be served from the (md)cache to improve performance. So enable that.Also, could you also enable client-io-threads and see if that improves performance?Which version of gluster are you using BTW?On Tue, Sep 5, 2017 at 4:32 AM, Abi Askushi <rightkicktech@xxxxxxxxx> wrote:______________________________Hi all,I have a gluster volume used to host several VMs (managed through oVirt).The volume is a replica 3 with arbiter and the 3 servers use 1 Gbit network for the storage.When testing with dd (dd if=/dev/zero of=testfile bs=1G count=1 oflag=direct) out of the volume (e.g. writing at /root/) the performance of the dd is reported to be ~ 700MB/s, which is quite decent. When testing the dd on the gluster volume I get ~ 43 MB/s which way lower from the previous. When testing with dd the gluster volume, the network traffic was not exceeding 450 Mbps on the network interface. I would expect to reach near 900 Mbps considering that there is 1 Gbit of bandwidth available. This results having VMs with very slow performance (especially on their write operations).The full details of the volume are below. Any advise on what can be tweaked will be highly appreciated.Volume Name: vms
Type: Replicate
Volume ID: 4513340d-7919-498b-bfe0-d836b5cea40b
Status: Started
Snapshot Count: 0
Number of Bricks: 1 x (2 + 1) = 3
Transport-type: tcp
Bricks:
Brick1: gluster0:/gluster/vms/brick
Brick2: gluster1:/gluster/vms/brick
Brick3: gluster2:/gluster/vms/brick (arbiter)
Options Reconfigured:
cluster.granular-entry-heal: enable
performance.strict-o-direct: on
network.ping-timeout: 30
storage.owner-gid: 36
storage.owner-uid: 36
user.cifs: off
features.shard: on
cluster.shd-wait-qlength: 10000
cluster.shd-max-threads: 8
cluster.locking-scheme: granular
cluster.data-self-heal-algorithm: full
cluster.server-quorum-type: server
cluster.quorum-type: auto
cluster.eager-lock: enable
network.remote-dio: off
performance.low-prio-threads: 32
performance.stat-prefetch: off
performance.io-cache: off
performance.read-ahead: off
performance.quick-read: off
transport.address-family: inet
performance.readdir-ahead: on
nfs.disable: on
nfs.export-volumes: onThanx,Alex_________________
Gluster-users mailing list
Gluster-users@xxxxxxxxxxx
http://lists.gluster.org/mailman/listinfo/gluster-users
_______________________________________________ Gluster-users mailing list Gluster-users@xxxxxxxxxxx http://lists.gluster.org/mailman/listinfo/gluster-users
