Scheduler: when evicting don't normalise actualShare #3899
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Signed-off-by: robersmi606 <[email protected]>
d80tb7
approved these changes
Sep 4, 2024
svc-gh-ghzonetrans-p
restored the
sendToGitHub/sched-no-div-total-cost
branch
svc-gh-ghzonetrans-p
restored the
sendToGitHub/sched-no-div-total-cost
branch
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Problem
There is currently a problem when
adjustedFairShareis capped by demand.The scheduler caps
adjustedFairSharetocostat https://git.c3.zone/GR/armada/blob/69232402e78d1a420d56374415436fe15d2ebf0e/internal/scheduler/context/scheduling.go#L174However, when deciding whether to evict a job, it compares fair share to
actualShare = cost / totalCostatarmada/internal/scheduler/preempting_queue_scheduler.go
Line 132 in 6923240
If
totalCost < 1(which it often is for gpu clusters), dividing bytotalCostinflatesactualShareso that it thinksactualShareis above fair share even for fairly undemanding users. So it evicts many jobs well below fair share.Solution
Get rid of the
/ totalCostatpreempting_queue_scheduler.go#L132This simplifies things, and makes it consistent between the two places. It also stops strange behavior for non-full clusters where totalCost may we well under 1, so actualShare gets inflated, and many jobs are evicted even though the cluster isn't full.