why does dfeast_scsrev only use half the available computational power?

[Gagan]

hi,

i asked this question ten years ago and i was told at that time it was due to something with the dual processor configuration and non-uniform memory architecture (NUMA).

however this is wrong, as i've been abusing (lol) my 2020 wintel macbook pro 16' i9 9980HX and it is still showing 49% when running scsrev.

this means there is something simple or trivial on your guys' (excuse my preference for convenience in the off-chance there are ladies on the team) end.

[Gagan]

i'm so good lol, i feel bad though because it's like i'm cracking a whip on the team's back

i wonder if i got the attention of the team's top dogg gennady--i know you watchin' fam! lol

[Fengrui]

Hello!

I tried the in-package example dfeast_sparse.c with some modifications. I kept the pattern of the matrix unchanged, but made it much larger with N=10000 to have a stable run for ~10 seconds. On a dual-socket Intel(R) Xeon(R) Platinum 8480+ node (112 physical cores in total, Ubuntu 22.04.1 LTS for OS), I observed CPU usages remained ~11200% (by "top" command) for ~ 10 seconds. The oneMKL version used was 2024.1.

The subspace size looks relatively small. How long does it take to complete the run in your case? Also I'm not an expert of istat you mentioned in the old post. The difference could also come from the measuring tools.

Thanks,

Fengrui