I think that the best test is to: 0. Set only 1 change in the infrastructure 1. Automatically create your VM 2. Install the necessary application on the VM from point 1 3. Restore from backup the state of the App 4. Run a typical workload on the app - for example a bunch of queries that are pushed against a typical DB 5. Measure performance during point 4 (for example time of execution) 6. Start over
Anything else is a waste of time. Best Regards, Strahil Nikolov На 24 юли 2020 г. 13:26:18 GMT+03:00, Stefan Hajnoczi <stefa...@redhat.com> написа: >On Thu, Jul 23, 2020 at 07:25:14AM -0700, Philip Brown wrote: >> Usually in that kind of situation, if you dont turn on sync-to-disk >on every write, you get benchmarks that are artificially HIGH. >> Forcing O_DIRECT slows throughput down. >> Dont you think the results are bad enough already? :-} > >The results that were posted do not show iSCSI performance in isolation >so it's hard to diagnose the problem. > >The page cache is used when the O_DIRECT flag is absent. I/O is not >sent >to the disk at all when it can be fulfilled from the page cache in >memory. Therefore the benchmark is not an accurate indicator of disk >I/O >performance. > >In addition to this, page cache behavior depends on various factors >such >as available free memory, operating system implementation and version, >etc. This makes it hard to compare results across VMs, different >machines, etc. > >Stefan _______________________________________________ Users mailing list -- users@ovirt.org To unsubscribe send an email to users-le...@ovirt.org Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/WH4KFRSFGJCKRVM2VUJGKY26DEX5R2DH/
