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PERF-KMEM(1) perf Manual PERF-KMEM(1)

NAME

perf-kmem - Tool to trace/measure kernel memory properties

SYNOPSIS

perf kmem [<options>] {record|stat}

DESCRIPTION

There are two variants of perf kmem:

'perf kmem [<options>] record [<perf-record-options>] <command>' to
record the kmem events of an arbitrary workload. Additional 'perf
record' options may be specified after record, such as '-o' to
change the output file name.

'perf kmem [<options>] stat' to report kernel memory statistics.

OPTIONS

-i <file>, --input=<file>

For stat, select the input file (default: perf.data unless stdin is a fifo)

-f, --force

Don’t do ownership validation

-v, --verbose

Be more verbose. (show symbol address, etc)

--caller

Show per-callsite statistics

--alloc

Show per-allocation statistics

-s <key[,key2...]>, --sort=<key[,key2...]>

Sort the output (default: frag,hit,bytes for slab and bytes,hit for page). Available sort keys are ptr, callsite, bytes, hit, pingpong, frag for slab and page, callsite, bytes, hit, order, migtype, gfp for page. This option should be preceded by one of the mode selection options - i.e. --slab, --page, --alloc and/or --caller.

-l <num>, --line=<num>

Print n lines only

--raw-ip

Print raw ip instead of symbol

--slab

Analyze SLAB allocator events.

--page

Analyze page allocator events

--live

Show live page stat. The perf kmem shows total allocation stat by default, but this option shows live (currently allocated) pages instead. (This option works with --page option only)

--time=<start>,<stop>

Only analyze samples within given time window: <start>,<stop>. Times have the format seconds.microseconds. If start is not given (i.e., time string is ,x.y) then analysis starts at the beginning of the file. If stop time is not given (i.e, time string is x.y,) then analysis goes to end of file.

SEE ALSO

perf-record(1)

2024-03-13 perf