biopattern-bpfcc8
Identify random/sequential disk access patterns.
Usage
biopattern [-h]
[-d
DISK]
[interval]
[count]
Overview
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.