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

# [NAME](#NAME)

biopattern - Identify random/sequential disk access patterns.

# [SYNOPSIS](#SYNOPSIS)

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

# [DESCRIPTION](#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](#REQUIREMENTS)

CONFIG\_BPF and bcc.

# [OPTIONS](#OPTIONS)

[-h](#h)

Show help message and exit.

[-d](#d)

Trace this disk only.

[interval](#interval)

Print output every interval seconds, if any.

[count](#count)

Number of interval summaries.

# [EXAMPLES](#EXAMPLES)

[Trace access patterns of all disks, and print a summary on Ctrl-C:](#Trace)

\# **biopattern**

[Trace disk sdb only:](#Trace~2)

\# **biopattern -d sdb**

[Print 1 second summaries, 10 times:](#Print)

\# **biopattern 1 10**

# [FIELDS](#FIELDS)

[TIME](#TIME)

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

[DISK](#DISK)

Disk device name.

%RND

Ratio of random I/O.

%SEQ

Ratio of sequential I/O.

[COUNT](#COUNT)

Number of I/O during the interval.

[KBYTES](#KBYTES)

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

# [OVERHEAD](#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](#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](#OS)

Linux

# [STABILITY](#STABILITY)

Unstable - in development.

# [AUTHOR](#AUTHOR)

Rocky Xing

# [SEE ALSO](#SEE_ALSO)

[biosnoop(8)](/man/enterprise-packages/bcc/biosnoop.8), [biolatency(8)](/man/enterprise-packages/bcc/biolatency.8), [iostat(1)](/man/enterprise-packages/bcc/iostat.1)

2022-02-21 USER COMMANDS

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Document: biopattern(8) from bcc 0.37.0-r3 (Chainguard OS)
Source: https://github.com/iovisor/bcc