[ovirt-users] Re: Speed Issues
Hey Strahil,
as always: thanks!
On 24/03/2020 12:23, Strahil Nikolov wrote:
Hey Chris,
What type is your VM ?
CentOS7.
Try with 'High Performance' one (there is a good RH
documentation on that topic).
I was googly-eying that as well. Will try that tonight :)
1. Check the VM disk scheduler. Use 'noop/none' (depends on
multiqueue is enabled) to allow the Hypervisor aggregate the I/O requests from multiple
VMs.
Next, set 'noop/none' disk scheduler on the hosts - these 2 are the optimal for
SSDs and NVME disks (if I recall corectly you are using SSDs)
Yeah the gluster disks do have noop already.
2. Disable cstates on the host and Guest (there are a lot of articles
about that)
Not sure its a CPU bottleneck in any capacity, but ill dig into this.
3. Enable MTU 9000 for Hypervisor (gluster node).
Already done.
4. You can try setting/unsetting the tunables in the db-workload
group and run benchmarks with real workload .
Will also check!
5. Some users reported that enabling TCP offload on the hosts
gave huge improvement in performance of gluster - you can try that.
Of course there are mixed feelings - as others report that disabling it brings
performance. I guess it is workload specific.
performance.write-behind-window-size: 64MB (shard size)
This one doubled my speed from 200mb to 400mb!!
I think this is where the meat is at.
-Chris.
--
Christian Reiss - email(a)christian-reiss.de /"\ ASCII Ribbon
support(a)alpha-labs.net \ / Campaign
X against HTML
WEB alpha-labs.net / \ in eMails
GPG Retrieval https://gpg.christian-reiss.de
GPG ID ABCD43C5, 0x44E29126ABCD43C5
GPG fingerprint = 9549 F537 2596 86BA 733C A4ED 44E2 9126 ABCD 43C5
"It's better to reign in hell than to serve in heaven.",
John Milton, Paradise lost.