-
Notifications
You must be signed in to change notification settings - Fork 110
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
Propeller slows down clang ~20% #181
Comments
Unfortunately, I reproduced that result on AMD Ryzen 7700.
Processor:
Used OS:
Kernel:
Perf version:
|
llvm18 use Fixed MBB ID(llvm/llvm-project@3d6841b). While autofdo now revert the code which support 'Fixed MBB ID' (ad3e924). I think it may be the reason. |
Has this issue been resolved?
|
I use this code snap(llvm/llvm-project@3d6841b) and propeller seems work well with llvm16(I think llvm17 is ok). The reason is:
|
I have tried to reproduce optimization clang with Propeller.
After all modifications described in #179 and #180, modified https://github.com/google/autofdo/blob/master/propeller_optimize_clang.sh started to work on my machine.
Unfortunately, the results looks very strange. Applying propeller to clang slows it down about 20%:
I used numactl to pin threads to HW cores. When I disables pins, the results were improved slightly, but, the gap between baseline and propeller continues to be significant:
In the case of pinned threads, propeller slightly decreased iTLB misses, while L1-icache-misses increased about 1.5x times.
Tested in RAM-disk on $ lscpu
Used OS:
Used linux kernel:
Gists:
with numactl:
https://gist.github.com/foxtran/b7fedfbb0bd036629448ce62d18bd7a6
without numactl:
https://gist.github.com/foxtran/fdc4abf8e2de127800f670b9edeeb9f2
Applied patches (with #179, #180):
for numactl:
Without numactl:
The text was updated successfully, but these errors were encountered: