1biopattern(8)               System Manager's Manual              biopattern(8)
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NAME

6       biopattern - Identify random/sequential disk access patterns.
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SYNOPSIS

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

12       This traces block device I/O (disk I/O), and prints ratio of random/se‐
13       quential I/O for each disk or the specified disk either on  Ctrl-C,  or
14       after a given interval in seconds.
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16       This works by tracing kernel tracepoint block:block_rq_complete.
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18       Since this uses BPF, only the root user can use this tool.
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REQUIREMENTS

21       CONFIG_BPF and bcc.
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OPTIONS

24       -h     Show help message and exit.
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26       -d     Trace this disk only.
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28       interval
29              Print output every interval seconds, if any.
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31       count  Number of interval summaries.
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EXAMPLES

34       Trace access patterns of all disks, and print a summary on Ctrl-C:
35              # biopattern
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37       Trace disk sdb only:
38              # biopattern -d sdb
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40       Print 1 second summaries, 10 times:
41              # biopattern 1 10
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FIELDS

44       TIME   Time of the output, in HH:MM:SS format.
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46       DISK   Disk device name.
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48       %RND   Ratio of random I/O.
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50       %SEQ   Ratio of sequential I/O.
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52       COUNT  Number of I/O during the interval.
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54       KBYTES Total Kbytes for these I/O, during the interval.
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OVERHEAD

57       Since  block  device  I/O  usually  has  a  relatively low frequency (<
58       10,000/s), the overhead for this tool is expected to be low or negligi‐
59       ble. For high IOPS storage systems, test and quantify before use.
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SOURCE

62       This is from bcc.
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64              https://github.com/iovisor/bcc
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66       Also  look  in  the bcc distribution for a companion _examples.txt file
67       containing example usage, output, and commentary for this tool.
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OS

70       Linux
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STABILITY

73       Unstable - in development.
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AUTHOR

76       Rocky Xing
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SEE ALSO

79       biosnoop(8), biolatency(8), iostat(1)
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83USER COMMANDS                     2022-02-21                     biopattern(8)