NAME
hotspot.d - print disk event by location. Uses DTrace.
SYNOPSIS
hotspot.d
DESCRIPTION
hotspot.d is a simple DTrace script to determine if disk activity is occuring in the one place - a "hotspot". This helps us understand the system's usage of a disk, it does not imply that the existance or not of a hotspot is good or bad (often may be good, less seeking).
Since this uses DTrace, only users with root privileges can run this command.
EXAMPLES
- Sample until Ctrl-C is hit then print report,
-
# hotspot.d
FIELDS
- Disk
-
disk instance name
- Major
-
driver major number
- Minor
-
driver minor number
- value
-
location of disk event, megabytes
- count
-
number of events
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
hotspot.d will sample until Ctrl-C is hit.
AUTHOR
Brendan Gregg [Sydney, Australia]
SEE ALSO
dtrace(1M)