Houston, we have a problem: big file copying, USB, external disks

[John Zupfel <jzupfel@yahoo.co.uk>]

Are recent kernels (since somewhere around 2.6.27 - 2.6.28)
choking on big file copying?


https://bugs.launchpad.net/ubuntu/+source/gvfs/+bug/197762?comments=all

Quoting the latest post:
> No, it's not Ubuntu specific and Canonical didn't cause it.
> 
> Right now I'm copying between two SATA drives, connected to my PC via
> eSATA.  So far a lousy 600MB has been copied and I'm already down to
> 5MB/s and falling.
> 
> Here is what I know about the problem:
> 
> It affects ALL hardware.
> 
> It affects ALL file copying connections to varying degrees: USB,
> network, SATA/eSATA.
> 
> In some instances, it also affects multitasking, all but locking the
> computer up despite little to no CPU use in System Monitor.
> 
> There are no error logs, messages or anything else that occur when the
> problem is happening.
> 
> In my experience, if you test for the problem and nothing seems to be
> wrong, then that's because you aren't copying enough data, you don't
> know how fast your hardware should be copying files, or you are lucky
> enough to only be subtly affected that time.  Try copying more multi-
> gigabytes of data, several times and see if you can't get wildly
> different durations for the same data size.  As I state above, all
> hardware I have tested is affected to varying degrees, some hardware
> shows minor performance degradation over time, some hardware is all but
> useless for file copying.
> 
> If you ask me, it's either the scheduler (GUI lockups with no CPU usage
> makes me think this) or whatever performs the actual file copy process.
> It's definitely not a USB problem because it affects network copying
> too.