-
Notifications
You must be signed in to change notification settings - Fork 463
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
Reorder load and scaling code to allow latency hidding for block-wise scaled GEMMs #2600
Closed
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
This pull request was exported from Phabricator. Differential Revision: D57473133 |
✅ Deploy Preview for pytorch-fbgemm-docs ready!
To edit notification comments on pull requests, go to your Netlify site configuration. |
htyu
added a commit
to htyu/FBGEMM
that referenced
this pull request
May 17, 2024
… scaled GEMMs (pytorch#2600) Summary: The compiler may not do a good job at reordering instructions for better latency hiding due to various reasons. Thus I'm tweaking the kernel code here. Previously in the block-wise scaled GEMM kernel, the scaling logic followed `tl.load` and the compiler was not able to move the logic before the loads once the loads are pipelined. This created a situation where the scaling logic was blocked by the load barriers, which is unnecessary as they are independent. Since the barrier is only needed by the `dot` operation, I'm moving the scaling logic before the loads. {F1640448911} While we should fix the compiler to be more robust, I'm making a source change as a workaround. Differential Revision: D57473133
This pull request was exported from Phabricator. Differential Revision: D57473133 |
… scaled GEMMs (pytorch#2600) Summary: The compiler may not do a good job at reordering instructions for better latency hiding due to various reasons. Thus I'm tweaking the kernel code here. Previously in the block-wise scaled GEMM kernel, the scaling logic followed `tl.load` and the compiler was not able to move the logic before the loads once the loads are pipelined. This created a situation where the scaling logic was blocked by the load barriers, which is unnecessary as they are independent. Since the barrier is only needed by the `dot` operation, I'm moving the scaling logic before the loads. {F1640448911} While we should fix the compiler to be more robust, I'm making a source change as a workaround. Differential Revision: D57473133
htyu
added a commit
to htyu/FBGEMM
that referenced
this pull request
May 20, 2024
… scaled GEMMs (pytorch#2600) Summary: The compiler may not do a good job at reordering instructions for better latency hiding due to various reasons. Thus I'm tweaking the kernel code here. Previously in the block-wise scaled GEMM kernel, the scaling logic followed `tl.load` and the compiler was not able to move the logic before the loads once the loads are pipelined. This created a situation where the scaling logic was blocked by the load barriers, which is unnecessary as they are independent. Since the barrier is only needed by the `dot` operation, I'm moving the scaling logic before the loads. {F1640448911} While we should fix the compiler to be more robust, I'm making a source change as a workaround. Differential Revision: D57473133
This pull request has been merged in 3f4d79e. |
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.
Summary:
The compiler may not do a good job at reordering instructions for better latency hiding due to various reasons. Thus I'm tweaking the kernel code here.
Previously in the block-wise scaled GEMM kernel, the scaling logic followed
tl.load
and the compiler was not able to move the logic before the loads once the loads are pipelined. This created a situation where the scaling logic was blocked by the load barriers, which is unnecessary as they are independent. Since the barrier is only needed by thedot
operation, I'm moving the scaling logic before the loads.{F1640448911}
While we should fix the compiler to be more robust, I'm making a source change as a workaround.
Differential Revision: D57473133