PMC.SOFT(3)

💅 PMC.SOFT(3) — bestie's guide to software events ✨

okay so this is the pmc.soft page from the Library Functions Manual, and it's genuinely iconic — it's all about getting your measurements from software based events instead of poking at actual hardware counters. no cap, it's giving "the CPU is telling on itself" energy 🎀

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🌸 LIBRARY 🌸

Performance Counters Library (libpmc, -lpmc) — yes bestie, that's the one you link with 💖

✨ SYNOPSIS ✨

#include <pmc.h>

that's literally it, that's the whole vibe. one include and you're in 🦋

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💜 DESCRIPTION 💜

So the way this works: software events are the move when you wanna collect, like, various sources of software events. that's the whole point, fr fr. it's not about the silicon counting things — it's the kernel-side software hooks doing the counting for you 🔥

👑 PMC Features 👑

There are 16 sampling counters using software events, built on various sources. These PMCs support the following capabilities:

• PMC_CAP_CASCADE — No 🙈
• PMC_CAP_EDGE — No
• PMC_CAP_INTERRUPT — Yes ⭐
• PMC_CAP_INVERT — No
• PMC_CAP_READ — Yes ⭐
• PMC_CAP_PRECISE — No
• PMC_CAP_SYSTEM — Yes ⭐
• PMC_CAP_TAGGING — No
• PMC_CAP_THRESHOLD — No
• PMC_CAP_USER — Yes ⭐
• PMC_CAP_WRITE — Yes ⭐

so like, interrupts, reads, system, user, writes? slay. cascading, edge, invert, precise, tagging, threshold? not today bestie 💅

🧚 Event Qualifiers 🧚

Heads up: there is no supported event qualifier. so don't come looking for one, she's not here 😭

The event specifiers supported by software are:

• CLOCK.HARD — hard clock ticks. the classic ⏰
• CLOCK.STAT — stat clock ticks. statistics o'clock 🕰️
• CLOCK.PROF — profiling clock ticks. for when you wanna know where time's going 🎀
• INTR.ALL — interrupt filter executed. every single one, no filter on the filter ✨
• INTR.FILTER — interrupt filter returned FILTER_HANDLED. it handled it, queen 👑
• INTR.ITHREAD — interrupt filter returned FILTER_SCHEDULE_ITHREAD. scheduling an ithread, main character energy 🌟
• INTR.SCHEDULE — ithread scheduled. it's on the calendar bestie 📅
• INTR.STRAY — interrupt filter returned FILTER_STRAY. stray interrupts, we've all been there 💀
• INTR.WAITING — ithread not scheduled, already active. like texting someone who's already typing 🙈
• LOCK.FAILED — lock acquisition failed. the lock said no ❌
• PAGE_FAULT.ALL — all page fault type. every flavor of page fault 🌈
• PAGE_FAULT.READ — read page fault. reading, iconically 📖
• PAGE_FAULT.WRITE — write page fault. writing, also iconically ✍️

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🦋 SEE ALSO 🦋

like, go read these too, they're all linked and they all ate:

pmc(3), pmc.amd(3), pmc.atom(3), pmc.core(3), pmc.corei7(3), pmc.corei7uc(3), pmc.iaf(3), pmc.tsc(3), pmc.ucf(3), pmc.westmereuc(3), pmc_cpuinfo(3), pmclog(3), hwpmc(4)

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💖 HISTORY 💖

The pmc library first appeared in FreeBSD 6.0. a vintage icon, honestly 🍓

🌸 AUTHORS 🌸

The Performance Counters Library (libpmc, -lpmc) library was written by Joseph Koshy <jkoshy@FreeBSD.org>. and the Software PMC was written by Fabien Thomas <fabient@FreeBSD.org>. thank you both, kings 🫶

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💅 that's the whole page, bestie. no notes. periodt.

sign-off szn: this one's from Debian, dated September 23, 2021 — catch you on the next page, mwah 😘💜