Man page - biopattern-bpfcc(8)

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Manual

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

biopattern - Identify random/sequential disk access patterns.

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

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.

CONFIG_BPF and bcc.

Show help message and exit.
Trace this disk only.
Print output every interval seconds, if any.
Number of interval summaries.

# biopattern
# biopattern -d sdb
# biopattern 1 10

Time of the output, in HH:MM:SS format.
Disk device name.
%RND
Ratio of random I/O.
%SEQ
Ratio of sequential I/O.
Number of I/O during the interval.
Total Kbytes for these I/O, during the interval.

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.

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.

Linux

Unstable - in development.

Rocky Xing

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

2022-02-21 USER COMMANDS