Provided by: lmbench-doc_3.0-a7-1_all bug

NAME

       lat_pagefault - measure the cost of pagefaulting pages from a file

SYNOPSIS

       lat_pagefault  [ -P <parallelism> ] [ -W <warmups> ] [ -N <repetitions>
       ] file [ file....  ]

DESCRIPTION

       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 wire.)

       The benchmark maps in the entire file and the  access  pages  backwards
       using a stride of 256K kilobytes.

OUTPUT

       Output  format  is below; it prints the average cost of page faulting a
       page.

       Pagefaults on <file>: <d> usecs

BUGS

       Using a stride of 256K may be a bad idea because SCSI  controllers  may
       have caches bigger than that.

ACKNOWLEDGEMENT

       Funding   for  the  development  of  this  tool  was  provided  by  Sun
       Microsystems Computer Corporation.

SEE ALSO

       lmbench(8).

AUTHOR

       Carl Staelin and Larry McVoy

       Comments, suggestions, and bug reports are always welcome.

(c)1994 Larry McVoy                 $Date$                    LAT_PAGEFAULT(8)