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 I/O kernel functions using dynamic tracing and prints a historgram 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 kernel block I/O functions to update a histgroam, which are 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

SEE ALSO

       https://github.com/brendangregg/systemtap-lwtools/blob/master/disk/bitesize-nd.stp

USER COMMANDS                                      2016-02-05                                        bitesize(8)