69 lines
2.3 KiB
Groff
69 lines
2.3 KiB
Groff
.\" The following requests are required for all man pages.
|
|
.Dd May 18, 1995
|
|
.Os UNIX
|
|
.Dt BONNIE 1
|
|
.Sh NAME
|
|
.Nm bonnie
|
|
.Nd Performance Test of Filesystem I/O
|
|
.Sh SYNOPSIS
|
|
.Nm bonnie
|
|
.Op Fl d Ar scratch-dir
|
|
.Op Fl s Ar size-in-MB
|
|
.Op Fl m Ar machine-label
|
|
|
|
.Sh DESCRIPTION
|
|
.Nm Bonnie
|
|
tests the speed of file I/O from standard C library calls.
|
|
It reads and writes 8KB blocks to find the maximum sustained
|
|
data rate (usually limited by the drive or controller) and additionally
|
|
rewrites the file (better simulating normal operating conditions and
|
|
quite dependent on drive and OS optimisations).
|
|
|
|
The per character read and write tests are generally limited by CPU speed
|
|
only on current generation hardware. It takes some 35 SPECint92 to read
|
|
or write a file at a rate of 1MB/s using getc() and putc().
|
|
|
|
The seek test results depend on the buffer cache size, since the fraction
|
|
of disk blocks that fits into the buffer cache will be found without any
|
|
disk operation and will contribute zero seek time samples.
|
|
(See
|
|
.Sx BUGS
|
|
below.)
|
|
|
|
.Sh OPTIONS
|
|
.Bl -tag -width indent
|
|
.It Fl d Ar scratch-dir
|
|
Specify the directory where the test file gets written. The default
|
|
is the current directory. Make sure there is sufficient free space
|
|
available on the partition this directory resides in.
|
|
.It Fl s Ar size-in-MB
|
|
Specify the size of the test file in MByte. This much space must be
|
|
available for the tests to complete.
|
|
.It Fl m Ar machine-label
|
|
Specify a label to be written in the first column of the result table.
|
|
.El
|
|
|
|
.Sh SEE ALSO
|
|
.Xr iozone 1 ,
|
|
.Xr iostat 8
|
|
|
|
.Sh AUTHOR
|
|
.Nm Bonnie
|
|
was written by Tim Bray <tbray@watsol.waterloo.edu>.
|
|
|
|
.Sh BUGS
|
|
.Nm Bonnie
|
|
tries hard to measure disk performance and not the quality of the
|
|
buffer cache implementation. In merged buffer caches common today,
|
|
the buffer cache size is often only limited by total RAM on an otherwise
|
|
unloaded system. Be sure to use a file at least twice at large as
|
|
available RAM to protect against artificially high results.
|
|
|
|
There is no way to keep the buffer cache from increasing the reported
|
|
seek rate. This is because the fraction of accesses corresponding to the
|
|
amount of the file cached, will be done without seeks.
|
|
If your buffer cache is half the size of the file used, then half the
|
|
requests will be satisfied immediately, and the seek rate printed
|
|
will be twice the actual value.
|
|
|