bitesize.d1m
Analyse disk i/o size by process. uses dtrace.
Usage
bitesize.d
Overview
This produces a report for the size of disk events caused by processes. These are the disk events sent by the block I/O driver.
If applications must use the disks, we generally prefer they do so sequentially with large I/O sizes, or larger "bites".
Since this uses DTrace, only users with root privileges can run this command.
Examples
- Sample until Ctrl-C is hit then print report,
-
#
bitesize.d
Fields
PID
|
process ID |
|---|---|
CMD
|
command and argument list |
value
|
size in bytes |
count
|
number of I/O operations |
Notes
The application may be requesting smaller sized operations, which are being rounded up to the nearest sector size or UFS block size.
To analyse what the application is requesting, DTraceToolkit programs such as Proc/fddist may help.
Documentation
See the DTraceToolkit for further documentation under the Docs directory. The DTraceToolkit docs may include full worked examples with verbose descriptions explaining the output.
Exit
bitesize.d will sample until Ctrl-C is hit.
Releases
115 releases since Mac OS X 10.5; the text changed 1 time.