multiprocessing: Don't create pool many times #297
Merged
Conversation
This file contains hidden or 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
emaxx-google
force-pushed
the
test-mgr--single-process-pool
branch
from
e6fe607 to
4acdd3a
Compare
emaxx-google
changed the title
Have a single process pool instead of recreating it every time pass(es) are to be executed. We only need to make sure to cancel running jobs. This brings a significant speedup especially for small cases or for late stages of reductions in general, where it takes just a fraction of a second to discover a reduction. Now we don't have to pay the price for initializing the Pebble pool - hundreds of milliseconds - repeatedly. Empirical measurements show 1.5x-2x speedup for reductions that used to finished within 20 minutes.
emaxx-google
force-pushed
the
test-mgr--single-process-pool
branch
from
eb0c5d6 to
e7a1fc0
Compare
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Outdated suggestions cannot be applied.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.
Have a single process pool instead of recreating it every time pass(es)
are to be executed. We only need to make sure to cancel running jobs.
This brings a significant speedup especially for small cases or for late
stages of reductions in general, where it takes just a fraction of a
second to discover a reduction. Now we don't have to pay the price for
initializing the Pebble pool - hundreds of milliseconds - repeatedly.
While empirical measurements show 1.5x-2x speedup, unfortunately
most of it will be "eaten" by the switch to "forkserver" multiprocessing
mode - the latter seems unavoidable to fix occasional deadlocks.