Hi, I can't fully confirm your observation, but since we upgraded to Caracal a couple of weeks ago, we feel like there has been a performance decrease using the Dashboard Instances Tab (which also uses nova-api, of course). I haven't had the time to dig deeper, and we also don't have any historical data to compare to, unfortunately. But after we upgraded to Antelope earlier this year, me and my colleagues felt like the Dashboard performance was better than in earlier releases. And now on Caracal the opposite is being reported. And even worse: we've seen gateway timeouts a few times for the first time in 5 or 6 years, I don't exactly remember. Back then it was some memcached misconfiguration, and we haven't changed anything in memcached in the past years, maybe we should though. I'm very curious if others have observed similar things. Regards, Eugen Zitat von Chang Xue <cxue22@bloomberg.net>:
Hello, we recently upgraded from Bobcat to Caracal. After upgrading, an interesting increment of duration of nova api call is observed.
It's involved to multiple API calls, e.g. os-query-sets, /v2.1/servers/detail, etc. And it seems to be accumulated, meaning whenever nova-api is restarted, the duration seems to be fairly fast, giving response within like 80, 90 ms. As it keeps running for like up to 10 days, the duration increases to over 500 ms.
I noticed that Caracal is using UnifiedLimitsDriver instead of DbQuotaDriver. I tried to change nova.conf to use DbQuotaDriver but it seems not working well with reducing the duration. I understand that calling to Keystone and Placement (and likely other external APIs) could result to longer duration, but pretty confused why it shows up as accumulated.
Wondering if anyone else in Openstack community noticed the similar issue, thanks!