-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Friday 2007-04-20 at 09:37 +0200, Franz Petri wrote:
Hi,
I have a problem getting the performance up when writing to an external harddisk, connected via usb 2.0.
It shows when doing: i) cp file_from_local_sata_hdd to_usb_hdd_formatted_with_ext3fs_or_reiserfs ii) tar -xf file_from_local_sata_hdd -C/directory_on_usb_hdd_formatted_with_ext3fs_or_reiserfs iii) dd if=file_from_local_sata_hdd of=to_usb_hdd_formatted_with_ext3fs_or_reiserfs iv) all other stuff that incorporates writing to the disk, like creating encfs-files on it or trying to setup an encrypted loop device with yast on it.
I would guess tar running slower in 'ii' above.
CASE 2, "default" writing to the usb hdd, one can replace dd with cp or tar at will, the figures stay the same:
dd if=/dev/zero of=/media/usbdisk/tmp/tmp.txt count=1000 1000+0 records in 1000+0 records out 512000 bytes (512 kB) copied, 3.26417 seconds, 157 kB/s
CASE 3, notice the increased bs:
dd if=/dev/zero of=/media/usbdisk/tmp/tmp.txt count=4 bs=128K 4+0 records in 4+0 records out 524288 bytes (524 kB) copied, 0.033982 seconds, 15.4 MB/s
So the block size affects a lot. Curious! My guess then would be that you perhaps are mounting "sync" mode, which is very slow. Or the newer intermediate mode I forgot the name. You could also benefit of mounting "noatime". Issue the command "mount" and see what you have.
I have created the ext3 and reiser partitions on the usb hdd with the yast partitioner, basically leaving everything at default settings.
There is a possibility I have not explored, and is having the journal in the local filesystem instead, but I'm not sure how to accomplish that. I think it would speed up things noticeably. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) Comment: Made with pgp4pine 1.76 iD8DBQFGKWbhtTMYHG2NR9URAiHvAJ97aAagg5p9TN7VcxCMrI21L7EOlgCdHMuh sM5ATNxjGQLcaa8pAFKL+1k= =oV/O -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org