Section 8 · System administration

bcc-bitesize.8

Package: bcc-tools

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bitesize

NAME
SYNOPSIS
DESCRIPTION
REQUIREMENTS
EXAMPLES
FIELDS
OVERHEAD
SOURCE
OS
STABILITY
AUTHOR
SEE ALSO

NAME

bitesize − Summarize block device I/O size as a histogram − Linux eBPF/bcc.

SYNOPSIS

bitesize

DESCRIPTION

Show I/O distribution for requested block sizes, by process name.

This works by tracing block:block_rq_issue and prints a histogram of I/O size.

Since this uses BPF, only the root user can use this tool.

REQUIREMENTS

CONFIG_BPF and bcc.

EXAMPLES

Count I/O size per process until Ctrl-C is hit:

bitesize

FIELDS


	Kbtes		Size in kilobytes of range
	count		How many I/O fell into this range

distribution

An ASCII bar chart to visualize the distribution (count column)

OVERHEAD

This traces a block I/O tracepoint to update a histogram, which is asynchronously copied to user-space. This method is very efficient, and the overhead for most storage I/O rates (< 10k IOPS) should be negligible. If you have a higher IOPS storage environment, test and quantify the overhead before use.

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

Allan McAleavy