Re: Sync file on write?

On Sun, 27 Dec 2009, Paul Hartman wrote:


I have a USB device and write speed is terrible when I copy more than
1 file to it (it is mounted in async mode). If I copy just one file
and sync, speed is 17MB/sec, if I copy more than 1 file the speed
drops well below 2MB/sec. This does not happen on MS Windows so I
think it's some side-effect of linux i/o flushing creating multiple
write-streams or something like this.

Anyway, I'm trying to work-around this and wonder if there is a way I
can tell MC to sync/fsync (whatever means ensure file is written to
disk physically) after each file? If it would apply only to writes
into this device that would be even better :)



I have no idea of the cause of this. I am not a specialist in Midnight Commander to any extent whatsoever. I do know a bit more about USB, but I have never delved very much into questions of speed.

Keeping the above disclaimers in mind, it does appear to me that there is a simple test which might help to localize the problem.

Can you set up a situation in which the slowdown occurs in Midnight Commander, but it is possible to move the same files from the same source location to the same destination using command-line tools only? And run a time comparison under both circumstances?

Theodore Kilgore

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]