---
name: "slabratetop-bpfcc"
section: "8"
platform: "linux"
package: "bpfcc-tools"
version: "0.31.0+ds-7"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/slabratetop-bpfcc"
---

# slabratetop-bpfcc(8)

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

## 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)](/slabtop/1.md), 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)](/slabtop/1.md)