avi performance

anarchist · Apprentice Joined: 12 Jul 2002 Posts: 264

okay, i got an annoying problem. When i copy some avi files from my harddisk to another (it does not matter which file system i use, but my linux harddisk is ext3) the performance is very very low. I get around 2.0 mb/s, and because of this i can't use my 24x cdr at full speed and this is really somewhat annoying.
The interesting thing is, it makes no difference how big the avi file is (i actually think this problem is related to divx, because all these avis were divx files.) and when i copy a 700mb iso file around i get about 30 mb/s ! so apparently its not a matter of size. But i'm not quiet sure about that.
Some last info, dma is enabled, and all performance related things i could enable for my hdd are enabled. The performance is also bad if i copy the files around on the same harddrive, so copying avi files around no matter where or what size, results always in speeds below 2mb/s

I hope somebody has a clue

zen_guerrilla · Guru Joined: 18 Apr 2002 Posts: 343 Location: Greece

avi's are normal binary files, nothing fancy. If you can get 30 mb/s when transfering a 700mb iso from one disk to another you should get the same bandwidth when transfering an avi. But if both discs are on same channel (master & slave) u should not have the maximum bandwidth (no matter what file u transfer).
Check your dma settings with 'hdparm /dev/hdX' & what your disk supports with 'hdparm -i /dev/hdX'.
For the cd-r you should use burnproof or what is supported on your drive. Try 'cdrecord -dev=X,Y,Z driveropts=help -checkdrive' (man cdrecord for more details).

p.s. : How do u count the transfer rate when copying files around ? I currently have a divx avi on my ~ dir and would like to test copying it around.

.:: zen ::.

anarchist · Apprentice Joined: 12 Jul 2002 Posts: 264

thx, its not a problem with the channel, it really doesn't matter from which location to which destination i'll copy these avi files, copying avis on my system is just plainly slow

I measured with kde, i know this is not really precise but, who the hell cares :wink:

Mhhh actually i could improve speed a little by turning on a kernel option, something with i/o taskfile access, but i actually forgot what name it really was

kang · Retired Dev Joined: 17 May 2002 Posts: 60

IDE taskfile I/O

alsa hdparm -I /dev/xxx
gives u slighty more info:)

anarchist · Apprentice Joined: 12 Jul 2002 Posts: 264

@kang
i know that everything is set up fine and i get good results when i test my harddrive, this problem just occurs when i copy these damn avi files