[gentoo-user] Horrible TrueCrypt performance

[Alex Schuster <wonko@wonkology.org>]

Hi there!

I have to copy some 100 G of files from one to another USB drive. Both
are formatted with NTFS, the destination drive already has a truecrypt
container file where I need to store the data into.

This is sort of working, but the speed is waayyyy too slow. After about
four hours, only 8 G were copied.

Looking at the cp -r output shows I see a bunch of files being
processed, then the output stops for some minutes. Sometimes for half an
hour.

Top shows the mount.ntfs-3g process writing to the destination using all
resources of one of my two cores. iotop -d 10 shows this process mainly.
What I find strange is that this process is also reading from the drive
I am copying to, 1600 K/s compared to 260 K/s writing speed. Huh?? And
sometimes there is no I/O from this process during the ten seconds of
sampling time. I sampled for about half an hour, and iotop -oa shows
that only 20 MB were written. This will never finish.

I used this command to mount the truecrypt container:
truecrypt --fs-options=uid=1000,umask=0007 -k /home/wonko/my.key
/media/My USB Drive/my_container /mnt
Adding 'async' to the fs-options did not help.

Any ideas? I've never used TrueCrypt before.

	Wonko