On Tue, Jan 5, 2010 at 5:32 AM, Timo Pelkonen <peltsip@xxxxxxxxx> wrote: > > > 5. tammikuuta 2010 13.29 Kimmo Hämäläinen <kimmo.hamalainen@xxxxxxxxx> > kirjoitti: >> >> Hi, >> >> On Sun, 2009-12-27 at 22:38 +0100, ext Paul Hartman wrote: >> > Hi, >> > >> > I'm using linux kernel 2.6.32 on my PC and mount N900 in mass storage >> > mode using vfat (async). >> > >> > If I write one file then sync/umount, write speed is about 17MB/sec, >> > same as I get on Windows Vista. However, if I write more than one file >> > and then sync/umount, speed is terrible, around 2MB/sec (and in kernel >> > 2.6.31 that speed was about 450kb/sec using the old pdflush code). So >> > it seems linux is maybe creating multiple write streams and N900 >> > doesn't deal with that well at all. >> >> There has been some USB speed-ups since the sales release, but I'm not >> sure if they fix this multiple file copying problem. I think it's best >> to file a bug to maemo.org, so Maemo kernel guys get the word (I think >> too few of them read this mailing list). >> >> -Kimmo >> >> > Size doesn't seem to matter, copying one 1gb file followed by sync is >> > around 8 times faster than copying 2 500gb files followed by sync. In >> > other words, as long as every single file copy is followed immediately >> > by sync before moving on to the next file, speed is fine. If more than >> > 1 file is copied before sync, it's bad. >> > >> > Does anyone else experience the same problem or have any ideas how to >> > solve it? I'm no USB guru an every other USB device I have seems to >> > work properly and at full speed. dmesg shows no messages (on PC) and >> > it is running USB 2.0 etc. >> > >> > So far my only workaround is to copy/sync/copy/sync/copy/sync but >> > that's annoying. However, the difference of taking 1 minute to write >> > 1gb versus taking 20 minutes to write 1gb is also annoying. >> > >> > Thanks :) >> > > I suggest you try to change your settings in linux first > http://talk.maemo.org/showpost.php?p=453521&postcount=24 > Ossipena / Timo Thanks Timo, I actually wrote that post :) Sorry I forgot to follow-up here. Yes, it seems CFQ for whatever reason is really slow with N900 (for me). I don't know who is to "blame" (scheduler, vfat, n900, flash memory, usb mass storage drivers...) but I'm happy to find a work-around... and happy for modular i/o schedulers in linux :) Thanks Paul _______________________________________________ maemo-users mailing list maemo-users@xxxxxxxxx https://lists.maemo.org/mailman/listinfo/maemo-users
