Comment 34 for bug 336652

I'm not sure if this is related or not, but I'm getting similar behaviour on my own system, but *only* when copying files *from* my USB memory stick (a 4 GB Corsair Flash Voyager) *to* the internal SSD on my Asus Eee PC 900 running Ubuntu 8.10 with a custom build of Linux 2.6.27 (probably slightly patched) provided by array.org.

I.e. reading a file from the USB stick to /dev/null, no slowdown.
Writing /dev/zero to USB stick, no slowdown.
Reading a file from the internal SSD to /dev/null, no slowdown.
Writing /dev/zero to internal SSD, no slowdown.
Copying a file from internal SSD to USB stick, no slowdown.
Copying a file from USB stick to internal SSD, I get massive slowdowns on interactive performance. Launching a terminal, which usually takes a few seconds, suddenly takes the better part of a minute.

Linux used is 2.6.27-8-eeepc on i686 SMP, as prebuilt by http://www.array.org/ubuntu/

The filesystem on the internal SSD is ext3, running on LVM, running on LUKS (encrypted filesystem). As set up by the Ubuntu 8.10 installer. Swap is also on the same encrypted LVM.

The filesystem on the USB stick is vfat. Nothing fancy at all.

I should also add that the read performance of my USB stick is faster (about 25 MB/s) than the write performance on the built-in SSD (about 10 MB/s).

If you feel that it is useful, I can provide dumps of lspci/lsusb/lsmod or any other information. As for the exact build options and patches, that should be determinable by checking the web site specified above.

Hope more data makes it possible to determine a pattern to this bug.