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cosmoss-jigu / memtis

Tiered memory management
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PEBS samples generated on a single core #6

Open SujayYadalam94 opened 4 months ago

SujayYadalam94 commented 4 months ago

I am running on Memtis on a IceLake machine with 24 cores. I added some stats to the kernel to count the number of PEBS samples generated on each core. I see that PEBS samples are collected only on 1 core, I have tested with multiple applications: XSBench, pagerank, GUPS, Silo.

However when I disable PID in the below line in linux/mm/htmm_sampler.c:80 event_fd = htmm__perf_event_open(&attr, __pid, cpu, -1, 0); to event_fd = htmm__perf_event_open(&attr, -1, cpu, -1, 0); I see samples generated on all cores.

Do you have any idea about this? Did having the pid parameter work on your machine?

SujayYadalam94 commented 4 months ago

As a follow-up, I want to share that disabling the PID (setting it to -1), generating samples on all cores improves performance.