Re: Large Partition Performance Test

[Hans Reiser <reiser@namesys.com>]

Bill Rees wrote:

>I upgraded my kernel to 2.4.19-pre6 with the speedup
>patch installed and still see similiar results as
>before.  As the amount of data on the partition
>increases, my write performance slows.  This time, I
>simply modified a previously posted script to mimic my
>production application.  The test is still running and
>will take quite awhile to fill the disk.  Each line of
>the output represents 1.68gb of disk space.
>
>Test system:
>------------
>
>Dual Athlon MP 1600+
>512 gb system memory
>3ware 7450 disk switch configured for RAID 5 (6x160
>Maxtor drives) formatted to 800gb
>custom distribution of Linux using aformentioned
>kernel
>
>Results:
>--------
>
>day/hour 00 00 seconds = 259
>day/hour 00 01 seconds = 278
>day/hour 00 02 seconds = 290
>day/hour 00 03 seconds = 302
>day/hour 00 04 seconds = 314
>day/hour 00 05 seconds = 328
>day/hour 00 06 seconds = 339
>day/hour 00 07 seconds = 352
>day/hour 00 08 seconds = 365
>day/hour 00 09 seconds = 375
>day/hour 00 10 seconds = 386
>day/hour 00 11 seconds = 393
>day/hour 00 12 seconds = 405
>day/hour 00 13 seconds = 416
>day/hour 00 14 seconds = 425
>day/hour 00 15 seconds = 434
>day/hour 00 16 seconds = 446
>day/hour 00 17 seconds = 457
>day/hour 00 18 seconds = 468
>
>Script:
>-------
>
>#!/bin/sh
>block_size=1024
>blocks_count=15
>for d1 in 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14
>15 16 17 18 19 20 21 22 23 24 25; do
>    for h1 in 00 01 02 03 04 05 06 07 08 09 10 11 12
>13 14 15 16 17 18 19 20 21 22 23; do
>        echo -n "day/hour $d1 $h1 seconds = "
>        begin_time=`date +%s`
>        for m1 in 00 01 02 03 04 05 06 07 08 09 10 11
>12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
>30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 46 47 48
>49 50 51 52 53 54 55 56 57 58 59 ; do
>            mkdir -p /video00/$d1/$h1$m1
>            for s1 in 00 01 02 03 04 05 06 07 08 09 10
>11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
>29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46
>47 48 49 50 51 52 53 54 55 56 57 58 59; do
>                for f1 in 00 01 02 03 04 05 06 07 08
>09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
>27 28 29; do
>                    dd if=/dev/zero
>of=/video00/$d1/$h1$m1/$s1$f1 \
>                        bs=$block_size
>count=$blocks_count \
>                        >/dev/null 2>&1
>                done
>            done
>        done
>        end_time=`date +%s`
>        echo $(($end_time - $begin_time))
>    done
>done
>
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Interesting, please investigate Edward and Oleg....

Hans