feat: warm caches during app startup #3500
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
bhearsum
force-pushed
the
push-zwkqnnxyxxuk
branch
4 times, most recently
from
634140a to
737419e
Compare
ahal
approved these changes
Jul 29, 2025
bhearsum
force-pushed
the
push-zwkqnnxyxxuk
branch
3 times, most recently
from
2509818 to
eb295c2
Compare
This will be useful when warming caches.
This code runs before the public app begins accepting requests, which should mean that we don't need to hit the database very much after beginning to serve requests. Doing this at start-up also means we fetch the releases sequentially, which should (slightly) spread the load out more. I verified locally that the app is incapable of responding to requests until `public.py` finishes executing by adding a `time.sleep` to the end of it. While the sleep was running requests to the app hung. This means that `/__heartbeat__` requests won't complete successfully until caches have been warmed up. Hopefully this will help with database load during scaling events. See: https://mozilla-hub.atlassian.net/browse/SVCSE-3425
bhearsum
force-pushed
the
push-zwkqnnxyxxuk
branch
from
eb295c2 to
a6e8a05
Compare
ahal
approved these changes
Jul 31, 2025
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Outdated suggestions cannot be applied.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.
This code runs before the public app begins accepting requests, which should mean that we don't need to hit the database very much after beginning to serve requests. Doing this at start-up also means we fetch the releases sequentially, which should (slightly) spread the load out more.
I verified locally that the app is incapable of responding to requests until
public.pyfinishes executing by adding atime.sleepto the end of it. While the sleep was running requests to the app hung. This means that/__heartbeat__requests won't complete successfully until caches have been warmed up.Hopefully this will help with database load during scaling events. See: https://mozilla-hub.atlassian.net/browse/SVCSE-3425