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slabratetop - Kernel SLAB/SLUB memory cache allocation rate top. Uses Linux

slabratetop(8) System Manager's Manual slabratetop(8)

NAME

slabratetop - Kernel SLAB/SLUB memory cache allocation rate top. Uses Linux BPF/bcc.

SYNOPSIS

slabratetop [-h] [-C] [-r MAXROWS] [interval] [count]

DESCRIPTION

This is top for the the rate of kernel SLAB/SLUB memory allocations. It works by tracing kmem_cache_alloc() calls, a commonly used interface for kernel memory allocation (SLAB or SLUB). It summarizes the rate and total bytes allocated of these calls per interval: the activity. Compare this to slabtop(1), which shows the current static volume of the caches.
 
This tool uses kernel dynamic tracing of the kmem_cache_alloc() function.
 
Since this uses BPF, only the root user can use this tool.

REQUIREMENTS

CONFIG_BPF and bcc.

OPTIONS

-C
Don't clear the screen.
-r MAXROWS
Maximum number of rows to print. Default is 20.
interval
Interval between updates, seconds.
count
Number of interval summaries.

EXAMPLES

Summarize active kernel SLAB/SLUB calls (kmem_cache_alloc()), showing the top 20 caches every second:
# slabratetop
Don't clear the screen, and top 8 rows only:
# slabratetop -Cr 8
5 second summaries, 10 times only:
# slabratetop 5 10

FIELDS

loadavg:
The contents of /proc/loadavg
CACHE
Kernel cache name.
ALLOCS
Allocations (number of calls).
BYTES
Total bytes allocated.

OVERHEAD

If kmem_cache_alloc() is called at a high rate (eg, >100k/second) the overhead of this tool might begin to be measurable. The rate can be seen in the ALLOCS column of the output.

SOURCE

This is from bcc.
https://github.com/iovisor/bcc
Also look in the bcc distribution for a companion _examples.txt file containing example usage, output, and commentary for this tool.

OS

Linux

STABILITY

Unstable - in development.

AUTHOR

Brendan Gregg

SEE ALSO

slabtop(1)
2016-10-17 USER COMMANDS