NAME

       biopattern - Identify random/sequential disk access patterns.

SYNOPSIS

       biopattern [-h] [-d DISK] [interval] [count]

DESCRIPTION

       This  traces  block  device  I/O (disk I/O), and prints ratio of random/sequential I/O for
       each disk or the specified disk either on Ctrl-C, or after a given interval in seconds.

       This works by tracing kernel tracepoint block:block_rq_complete.

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

REQUIREMENTS

       CONFIG_BPF and bcc.

OPTIONS

       -h     Show help message and exit.

       -d     Trace this disk only.

       interval
              Print output every interval seconds, if any.

       count  Number of interval summaries.

EXAMPLES

       Trace access patterns of all disks, and print a summary on Ctrl-C:
              # biopattern

       Trace disk sdb only:
              # biopattern -d sdb

       Print 1 second summaries, 10 times:
              # biopattern 1 10

FIELDS

       TIME   Time of the output, in HH:MM:SS format.

       DISK   Disk device name.

       %RND   Ratio of random I/O.

       %SEQ   Ratio of sequential I/O.

       COUNT  Number of I/O during the interval.

       KBYTES Total Kbytes for these I/O, during the interval.

OVERHEAD

       Since block device I/O usually has a relatively low frequency (< 10,000/s),  the  overhead
       for this tool is expected to be low or negligible. For high IOPS storage systems, test and
       quantify 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

       Rocky Xing

SEE ALSO

       biosnoop(8), biolatency(8), iostat(1)