Welcome to randread.
This program is in the public domain.
It was originally written by Curt Sampson <cjs@cynic.net>.

Randread is a small, simple benchmark program that reads or writes
randomly chosen blocks or lengths of blocks from a file or raw disk
partition. This can be used to test both random and sequential read and
write performance.

This sort of test is useful for a quick estimate of the performance
of, e.g., some database applications, where the bottleneck is not the
bandwith of reading data from the disk, but the number of small I/O
requests that can be processed per second.

This program is designed for simplicity over accuracy. It's useful
for a quick idea of what the I/O performance will be like, but it
probably won't do a good job of telling you which device to use if the
differences in the randread benchmarks are minor.

Randread takes the following options:

    -b <blocksize>	The size of the blocks to read or write, in bytes.
			This also determines the boundaries on which the
			reads are made. This should be a power of two. The
			default is 8192 bytes (8 KB).

    -c <count>		The number of reads or writes to do over the course
			of the test. The default is 512.

    -l <length>		The length of each read or write, in blocks. The
			program will seek to a random location in all of
			the files given and then sequentially read or write
			<length> blocks from that 

    -W			Write data, rather than reading it. Zeros are
			written, so this makes the test destructive.

The remaining parameters should be the names of files from which to read
or write. These files will be logically concatenated and treated as one
long string of blocks from which the selection of a range to read or
write will be made. You may use only a part of a file by appending a
colon and a hyphen-separated start/end block range to the file name. For
example, "foo:1024-2048" will use only blocks 1024 up to and including
2047 of the file foo. If no range is specified, the entire file (less any
final partial block) will be used.


$Id: README,v 1.2 2002/09/11 06:14:50 cjs Exp $
