Re: Extremely poor umass transfer rates

From: Paulo Marques
Date: Thu Apr 28 2005 - 13:23:05 EST

Randy.Dunlap wrote:
[...]On Thu, 28 Apr 2005 19:55:40 +0200 Mark Rosenstand wrote:
| On Thu, 2005-04-28 at 12:59 -0400, Dave Jones wrote:
> [...]
| > USB1.1 is painfully slow for storage.
| | Yeah, but I don't think it should be 30 kB/s.

Yes it should be much more than 30kB/s. I remember measuring about 900kB/s.

| | Some more details:
| | | The line that 'hald' puts in fstab looks like this:
| | /dev/sdb /media/usbdisk vfat \
| user,exec,noauto,utf8,noatime,sync,managed 0 0

The "sync" flag is what is killing your performance. It is needed if you intend to remove your usb pen without warning, but if you are going to unmount carefully you don't need it at all.

Try mounting the device as root somewhere else without the "sync" flag and measure the performance that way, to see the difference.

I hope this helps,

Paulo Marques -

All that is necessary for the triumph of evil is that good men do nothing.
Edmund Burke (1729 - 1797)
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