.TH fsrw.d 1m "Apr 23, 2006" "version 0.50" "USER COMMANDS" .SH NAME fsrw.d \- file system read/write event tracing. Uses DTrace. .SH SYNOPSIS .B fsrw.d .SH DESCRIPTION This traces file related activity: system call reads and writes, vnode logical read and writes (fop), 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. 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 events, # .B fsrw.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 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 fsrw.d will trace until Ctrl\-C is hit. .SH AUTHOR Brendan Gregg [Sydney, Australia] .SH SEE ALSO fspaging.d(1M), dtrace(1M)