LIBPFM(3)

💖 LIBPFM — the libpfm_intel_hswep_unc_r3qpi era 💖

okay bestie, so this one lives in the Linux Programmer's Manual, section 3, and it's all about giving you support for the Intel Haswell-EP R3QPI uncore PMU. Yes it's a mouthful. Yes it slays. Let's go 🫶

✨ SYNOPSIS ✨

#include <perfmon/pfmlib.h>

• PMU name: hswep_unc_r3qpi[0-2]
• PMU desc: Intel Haswell-EP R3QPI uncore PMU

🌸 DESCRIPTION 🌸

So the library literally supports the Intel Haswell R3QPI uncore PMU. That's the vibe.

heads up: this PMU model only exists on Haswell model 63. not 62, not 64, only 63. iykyk 💅

🎀 MODIFIERS 🎀

The following modifiers are supported on Intel Haswell R3PQI uncore PMU:

• e — enable edge detection, aka count only when there's a state transition from no occurrence of the event to at least one occurrence. this one is a boolean modifier, and it must be combined with a threshold modifier (t) with a value greater or equal to one. no solo runs bestie, it's a duo 💖
• t — set the threshold value. when you set it to a non-zero value, the counter counts the number of R3QPI cycles in which the number of occurrences of the event is greater or equal to the threshold. this is an integer modifier with values in the range [0:15]. yes that's a real range, stay inside it 🌈
• i — invert the meaning of the threshold or edge filter. if set, the event counts when strictly less than N occurrences occur per cycle if threshold is set to N. when invert is set, then threshold must be set to a non-zero value. if set, the event counts when the event transitions from occurring to not occurring (falling edge) when edge detection is set. this is a boolean modifier 👑

👑 AUTHORS 👑

Stephane Eranian <eranian@gmail.com>

and that's the whole page, no cap. it's from the Linux Programmer's Manual, section 3, it's LIBPFM, and it's dated May, 2015. go forth and count those R3QPI cycles, bestie 🦋💜