Copying to a FAT32 drive causes mouse to jitter

Jimage · 08-20-2006, 05:52 AM

Whenever I write to one of my 80Gb HDDs, the mouse begins to jitter. The more I copy to it, the jumpier it gets. It's similar to what happens when the CPU isn't cooling properly and starts to overheat and skip processes. The only way to fix the problem was to restart the machine.

It works without fault under XP and I can read from it within Slack as much as I want without any hassles, and the other 80 works fine for both read and write in both OSes. They're both formatted to FAT32.

Does anybody know what the problem might be? I suspect it's probably a memory issue, but I've no idea how to diagnose or fix it.

Cheers.

[Edit] Btw, I'm using Slackware 10.2 with the stock 2.4.31 kernel, fwiw.

Sammael · 08-21-2006, 05:09 AM

i'm trying to solve the same issue, only the disk i copy to is an external usb 2.0 disk.

regarding your problem, do you have DMA turned on?

try (as root) hdparm -i /dev/hda # replace hda with your actual disk
if you'll see something like
using_dma (0)

try (as root) hdparm -d1 /dev/hda

hope it helps...

Jimage · 08-21-2006, 05:51 AM

hdparm /dev/hdc showed up use_dma, but it didn't with the -i flag. Unfortunately, I found that out after using hdparm -d1 /dev/hdc so I don't know if it was on beforehand. I'd say it was, as with -i it spat out 'DMA modes: mdma0 mdma1 mdma2'.

Thanks for the suggestion. Alas, the problem persists.

[edit] There seems to be a memory leak.

Code:

Before copy

Mem:    904496k total,   268288k used,   636208k free,    39344k buffers
Swap:   128484k total,        0k used,   128484k free,   121588k cached

Copied 95Mb

Mem:    904496k total,   570116k used,   334380k free,    60496k buffers
Swap:   128484k total,        0k used,   128484k free,   328704k cached

Copied 78Mb

Mem:    904496k total,   761868k used,   142628k free,    60696k buffers
Swap:   128484k total,        0k used,   128484k free,   487904k cached

Copied 4.0Gb

Mem:    904496k total,   897872k used,     6624k free,    33744k buffers
Swap:   128484k total,        0k used,   128484k free,   610640k cached

The mouse movement returns to normal and some of the RAM is regained if I delete the file afterward, but that's not very helpful. :\

Code:

Deleted 4.0Gb

Mem:    904496k total,   616044k used,   288452k free,    34192k buffers
Swap:   128484k total,        0k used,   128484k free,   326064k cached

Hmm... it also seems the same thing is happenening for both hard disks. I guess I hadn't tried copying to the first one before.