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*** /dev/null Thu May 18 20:25:21 1995
--- bonnie.1 Thu May 18 20:26:47 1995
***************
*** 0 ****
--- 1,68 ----
+ .\" 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 and the seek rate printed
+ will be twice the actual value.
+
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