admission: remove soft/moderate load slots#95590
admission: remove soft/moderate load slots#95590craig[bot] merged 1 commit intocockroachdb:masterfrom
Conversation
|
This change is |
sumeerbhola
left a comment
There was a problem hiding this comment.
Thanks for doing this!
Reviewed 8 of 8 files at r2, all commit messages.
Reviewable status:complete! 1 of 0 LGTMs obtained (waiting on @irfansharif)
pkg/util/admission/granter.go line 154 at r2 (raw file):
} //gcassert:inline
nit: there are some remaining names with HighLoad in them
pkg/util/admission/kv_slot_adjuster.go line 114 at r2 (raw file):
kvsa.granter.setTotalSlotsLocked( tryDecreaseSlots(kvsa.granter.totalSlots, true)) } else if float64(runnable) <= float64((threshold*procs)/4) {
this 1/4 threshold else block can go away now, since it is subsumed by the succeeding 1/2 threshold else block.
We originally introduced these notions in admission control (cockroachdb#78519) for additional threads for Pebble compaction compression. We envisioned granting these "squishy" slots to background activities and permit work only under periods of low load. In working through cockroachdb#86638 (as part of \cockroachdb#75066), we observed experimentally that the moderate-slots count was not sensitive enough to scheduling latency, and consequently latency observed by foreground traffic. Elastic CPU tokens, the kind now being used for backups, offer an alternative to soft slots. We've since replaced uses of soft slots with elastic CPU tokens. This PR just removes the now dead-code code around soft/moderate load slots (it's better to minimize the number of mechanisms in the admission package). Fixes cockroachdb#95590. Release note: None
811f56e to
f39eefb
Compare
irfansharif
left a comment
There was a problem hiding this comment.
bors r+
Reviewable status:
pkg/util/admission/granter.go line 154 at r2 (raw file):
Previously, sumeerbhola wrote…
nit: there are some remaining names with
HighLoadin them
Done.
pkg/util/admission/kv_slot_adjuster.go line 114 at r2 (raw file):
Previously, sumeerbhola wrote…
this 1/4 threshold else block can go away now, since it is subsumed by the succeeding 1/2 threshold else block.
Done.
|
Build failed: |
|
Unrelated flake; pinged #95664. bors r+ |
|
Build succeeded: |
We originally introduced these notions in admission control (#78519) for additional threads for Pebble compaction compression. We envisioned granting these "squishy" slots to background activities and permit work only under periods of low load. In working through #86638 (as part of #75066), we observed experimentally that the moderate-slots count was not sensitive enough to scheduling latency, and consequently latency observed by foreground traffic. Elastic CPU tokens, the kind now being used for backups, offer an alternative to soft slots. We've since replaced uses of soft slots with elastic CPU tokens.
This PR just removes the now dead-code code around soft/moderate load slots (it's better to minimize the number of mechanisms in the admission package). Fixes #88032.
Release note: None
First commit is from #95007.