Cached file read performance with 6.2-PRERELEASE

[Mark Kirkwood]

A few more tests with a slightly improved version of the program 
(attached): We (i.e FreeBSD) do noticeably better with bigger block sizes.

Cheers

Mark

Gentoo - 2.6.18-gentoo-r3:
-----------------------

$ ./readtest /data0/dump/file 8192 0
random reads: 100000 of: 8192 bytes elapsed: 1.2698s io rate: 645155193 
bytes/s
$ ./readtest /data0/dump/file 8192 1
sequential reads: 100000 of: 8192 bytes elapsed: 1.1329s io rate: 
723129371 bytes/s


$ ./readtest /data0/dump/file 32768 0
random reads: 25000 of: 32768 bytes elapsed: 1.1583s io rate: 707244595 
bytes/s
$ ./readtest /data0/dump/file 32768 1
sequential reads: 25000 of: 32768 bytes elapsed: 1.1178s io rate: 
732838631 bytes/s

$ ./readtest /data0/dump/file 65536 0
random reads: 12500 of: 65536 bytes elapsed: 1.1478s io rate: 713742417 
bytes/s
$ ./readtest /data0/dump/file 65536 1
sequential reads: 12500 of: 65536 bytes elapsed: 1.1012s io rate: 
743921133 bytes/s


FreeBSD - 6.2-PRERELEASE #7: Mon Nov 27 19:32:33 NZDT 2006 :
------------------------------------------------------------

$ ./readtest /data0/dump/file 8192 0
random reads: 100000 of: 8192 bytes elapsed: 4.4477s io rate: 184186327 
bytes/s
$ ./readtest /data0/dump/file 8192 1
sequential reads: 100000 of: 8192 bytes elapsed: 1.9797s io rate: 
413804878 bytes/s

$ ./readtest /data0/dump/file 32768 1
sequential reads: 25000 of: 32768 bytes elapsed: 1.7068s io rate: 
479965034 bytes/s
$ ./readtest /data0/dump/file 32768 0
random reads: 25000 of: 32768 bytes elapsed: 2.0076s io rate: 408040469 
bytes/s

$ ./readtest /data0/dump/file 65536 0
random reads: 12500 of: 65536 bytes elapsed: 1.7856s io rate: 458778279 
bytes/s
$ ./readtest /data0/dump/file 65536 1
sequential reads: 12500 of: 65536 bytes elapsed: 1.6611s io rate: 
493158866 bytes/s