[XLA:SPMD] Remove LookaheadUserSharding in sharding propagation. #17267
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
![copybara-service[bot]](https://avatars.githubusercontent.com/in/44061?s=60&v=4){kind=small}
copybara-service
bot
force-pushed
the
test_669066012
branch
2 times, most recently
from
95b8e29
to
864b8e6
Compare
When we infer the dot sharding from its operands, it is possible that both operands can improve the dot sharding. LookaheadUserSharding iterates the dot users and decides which dot operand sharding is preferred. This cl removes it for two reasons. 1. It is unnecessary. If we can predict the sharding from dot users, we can wait the sharding to be propagated from users. The propagted sharding from users can still help us make choice between dot operands. 2. The lookhead sharding may be wrong. LookaheadUserSharding is a heuristics. We cannot guarantee that the predicted sharding will hold in the dot users. Reverts b4ea979 PiperOrigin-RevId: 676140549
copybara-service
bot
force-pushed
the
test_669066012
branch
from
864b8e6
to
7b61179
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Outdated suggestions cannot be applied.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.
[XLA:SPMD] Remove LookaheadUserSharding in sharding propagation.
When we infer the dot sharding from its operands, it is possible that both operands can improve the dot sharding. LookaheadUserSharding iterates the dot users and decides which dot operand sharding is preferred. This cl removes it for two reasons.
Reverts b4ea979