fspaging.d.1m   [plain text]


.TH fspaging.d 1m  "Apr 23, 2006" "version 0.50" "USER COMMANDS"
.SH NAME
fspaging.d \- file system read/write and paging tracing. Uses DTrace.
.SH SYNOPSIS
.B fspaging.d
.SH DESCRIPTION
This traces file related activity: system call reads and writes,
vnode logical read and writes (fop), vnode putpage and getpage activity,
and disk I/O. It can be used to examine the behaviour of each I/O
layer, from the syscall interface to what the disk is doing. Behaviour
such as read-ahead, and max I/O size breakup can be observed.

This is a verbose version of fsrw.d, as this also traces paging activity.

Since this uses DTrace, only the root user or users with the
dtrace_kernel privilege can run this command.
.SH EXAMPLES
.TP
Trace file system read/write/paging events,
# 
.B fspaging.d
.PP
.SH FIELDS
.TP
Event
traced event (see EVENTS below)
.TP
Device
device, for disk I/O
.TP
RW
either Read or Write
.TP
Size
size of I/O in bytes
.TP
Offset
offset of I/O in kilobytes
.TP
Path
path to file on disk
.PP
.SH EVENTS
.TP
sc-read
system call read
.TP
sc-write
system call write
.TP
fop_read
logical read
.TP
fop_write
logical write
.TP
fop_getpage
logical get page
.TP
fop_putpage
logical put page
.TP
disk_io
physical disk I/O
.TP
disk_ra
physical disk I/O, read ahead
.PP
.SH IDEA
Richard McDougall, Solaris Internals 2nd Ed, FS Chapter.
.PP
.SH 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.
.SH EXIT
fspaging.d will trace until Ctrl\-C is hit. 
.SH AUTHOR
Brendan Gregg
[Sydney, Australia]
.SH SEE ALSO
fsrw.d(1M), dtrace(1M)