lat_pagefault - measure the cost of pagefaulting pages from a file
lat_pagefault [ -P <parallelism> ] [ -W <warmups> ] [ -N <repetitions>
] file [ file.... ]
lat_pagefault times how fast a page of a file can be faulted in. The
file is flushed from (local) memory by using the msync() interface with
the invalidate flag set. (Note that NFS does not send this over the
wire so this makes for a handy way to measure the cost of going across
The benchmark maps in the entire file and the access pages backwards
using a stride of 256K kilobytes.
Output format is below; it prints the average cost of page faulting a
Pagefaults on <file>: <d> usecs
Using a stride of 256K may be a bad idea because SCSI controllers may
have caches bigger than that.
Funding for the development of this tool was provided by Sun
Microsystems Computer Corporation.
Carl Staelin and Larry McVoy
Comments, suggestions, and bug reports are always welcome.
(c)1994 Larry McVoy $Date$