Re: Simple preformance test

["Yura Umanets" <umanets@priocom.com>]

Ivan Ivanov wrote:

>Oleg Drokin wrote:
>
>>Hello!
>>
>>On Thu, Apr 11, 2002 at 03:14:03PM +0300, Ivan Ivanov wrote:
>>
>>>                  dd if=/dev/zero of=testdir/$d1/$f1$f2$f3$f4 \
>>>                      bs=$block_size count=$blocks_count \
>>>                      >/dev/null 2>&1
>>>                  rm -f testdir/$d1/$f1$f2$f3$f4
>>>
>>This is the explanation of your speedup.
>>You try to write to a file, but there is not enough space and file is not
>>created, but you did not notice.
>>And then you delete nonexistent files, and no doubts this is very fast
>>operation ;)
>>
>>BTW, if you turn off tails, your numbers might get faster, but space usage
>>will get worse.
>>
>>Bye,
>>    Oleg
>>
>
>Filesystem           1k-blocks      Used Available Use% Mounted on
>/dev/hda7              1172672   1170676      1996 100% /mnt/test
>
>I know this but  df  shows 1996 blocks free
>
>------
>Ivan
>
Besides, I think you didn't use "smart" block alocation technics in your 
tests and the all ppl know, that performance degradates because of 
bitmap when used space grows up.

Oleg, is this correct?

-- 
Yury Umanets
IT Engineer of Priocom Corp.
ICQ: 55494590