Hi, On 2022-09-22 16:07:02 -0500, Justin Pryzby wrote: > On Sun, Aug 28, 2022 at 02:28:02PM -0700, Andres Freund wrote: > > > > > @@ -71,8 +69,6 @@ task: > > > > > fingerprint_key: ccache/freebsd > > > > > reupload_on_changes: true > > > > > > > > > > - # Workaround around performance issues due to 32KB block size > > > > > - repartition_script: src/tools/ci/gcp_freebsd_repartition.sh > > > > > create_user_script: | > > > > > pw useradd postgres > > > > > chown -R postgres:postgres . > > > > > -- > > > > > > > > What's the story there - at some point that was important for > > > > performance > > > > because of the native block size triggering significant > > > > read-modify-write > > > > cycles with postres' writes. You didn't comment on it in the commit > > > > message. > > > > > > Well, I don't know the history, but it seems to be unneeded now. > > > > It's possible it was mainly needed for testing with aio + dio. But also > > possible that an upgrade improved the situation since. > > Maybe freebsd got faster as a result of the TAU CPUs? > https://mobile.twitter.com/cirrus_labs/status/1534982111568052240 > > I noticed because it's been *slower* the last ~24h since cirrusci > disabled TAU, as Thomas commit mentioned. > https://twitter.com/cirrus_labs/status/1572657320093712384
Yea, I noticed that as well. It's entirely possible that something in the "hardware" stack improved sufficiently to avoid problems. > I have no idea if the TAU CPUs eliminate/mitigate the original > performance issue you had with AIO. But they have such a large effect > on freebsd that it could now be the fastest task, if given more than 2 > CPUs. I'm planning to rebase early next week and try that out. Greetings, Andres Freund
