tools/perf/Documentation/perf-mem.txt

Source file repositories/reference/linux-study-clean/tools/perf/Documentation/perf-mem.txt

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System
Linux kernel
Corpus path
tools/perf/Documentation/perf-mem.txt
Extension
.txt
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7353 bytes
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212
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

perf-mem(1)
===========

NAME
----
perf-mem - Profile memory accesses

SYNOPSIS
--------
[verse]
'perf mem' [<options>] (record [<command>] | report)

DESCRIPTION
-----------
"perf mem record" runs a command and gathers memory operation data
from it, into perf.data. Perf record options are accepted and are passed through.

"perf mem report" displays the result. It invokes perf report with the
right set of options to display a memory access profile. By default, loads
and stores are sampled. Use the -t option to limit to loads or stores.

Note that on Intel systems the memory latency reported is the use-latency,
not the pure load (or store latency). Use latency includes any pipeline
queuing delays in addition to the memory subsystem latency.

On Arm64 this uses SPE to sample load and store operations, therefore hardware
and kernel support is required. See linkperf:perf-arm-spe[1] for a setup guide.
Due to the statistical nature of SPE sampling, not every memory operation will
be sampled.

On AMD this use IBS Op PMU to sample load-store operations.

COMMON OPTIONS
--------------
-f::
--force::
	Don't do ownership validation

-t::
--type=<type>::
	Select the memory operation type: load or store (default: load,store)

-v::
--verbose::
	Be more verbose (show counter open errors, etc)

-p::
--phys-data::
	Record/Report sample physical addresses

--data-page-size::
	Record/Report sample data address page size

RECORD OPTIONS
--------------
<command>...::
	Any command you can specify in a shell.

-e::
--event <event>::
	Event selector. Use 'perf mem record -e list' to list available events.

-K::
--all-kernel::
	Configure all used events to run in kernel space.

-U::
--all-user::
	Configure all used events to run in user space.

Annotation

Implementation Notes