On Wednesday, October 9th, 2024 at 4:43 PM, Eduard Zingerman <eddyz87@xxxxxxxxx> wrote:
[...]
>
> Do you have the performance / memory usage stats for next vs this patch-set?
Hi Eduard.
Yes, I ran perf stat, and looked at max memory as reported by
`/usr/bin/time -v`. The difference is insignificant compared to
acmel/dwarves:next (a1241b0) [1]. See below.
In terms of speed I didn't expect an improvement. It might have
even gotten worse due to potential encoder threads synchronization
when accessing elf_functions table. The table is now built once, but
before the changes it was built once *per thread*.
As for memory, no difference is a little surprising as we now have one
table instead of N (where N is number of threads). But more stuff was
added to elf_function, so I guess it ate all potential gains.
Performance counter stats for './pahole -J -j8 --btf_features=encode_force,var,float,enum64,decl_tag,type_tag,optimized_func,consistent_func,decl_tag_kfuncs --btf_encode_detached=/dev/null --lang_exclude=rust ~/repo/bpf-dev-docker/linux/.tmp_vmlinux1' (31 runs):
acmel/dwarves:next
68,904,383,016 cycles ( +- 0.30% )
5.5862 +- 0.0304 seconds time elapsed ( +- 0.54% )
vs this patchset
68,235,717,886 cycles ( +- 0.30% )
5.5550 +- 0.0412 seconds time elapsed ( +- 0.74% )
Memory on acmel/dwarves:next
Maximum resident set size (kbytes): 1392640
Maximum resident set size (kbytes): 1394600
Maximum resident set size (kbytes): 1393788
Memory on this patchset:
Maximum resident set size (kbytes): 1393564
Maximum resident set size (kbytes): 1394840
Maximum resident set size (kbytes): 1392348
[1] https://github.com/acmel/dwarves/commit/a1241b095de948becfed882929dda7c4318e022a
