Hi, I built my system from source following the LFS 6.3 book to the letter(pretty sure). After that I went though a mix of the latest BLFS book 6.2 and the dev copy of the BLFS book. I am running gnome but I noticed this problem before that when I was running TWM right after I installed X. It seems that whenever my system is doing a write to the hard drive the entire screen freezes including text when typing and mouse movement. It is possible it has been going on before I had X but did not notice because I only used one tty. It is very annoying needless to say but havn't had much luck finding anything out there on what the problem might be! Oh yeah, the system doesn't lock up perminatly. Only for a second or two while it does the write and then resumes normal operation for another 5-7 seconds.

Thanks for your ideas!!

that should be easy enough to fix.
the first thing i think of is make sure your disk is being seen as the correct type and DMA is enabled etc.
there is a weird trade off with a desktop machine and x.
also xorg just runs like crap and eats way to much resources.
you always want x to be responsive and not yield to others to the point of frozen cursor. on the other hand sometimes i set my box like that so i get good solid real time hard drive writes.

next thing i guess would be to make x less "nice"
try some thing like
renice -2 -p `ps -C Xorg -o pid=`
or
renice -3 -p `ps -C Xorg -o pid=`
you can of course put this in boot up scripts if it works

another factor potentially at work is the latency settings for your video card.
check out
lspci -v
for your video card you will see something like
latency 0
try something like
setpci -v -s '03:00.0' latency_timer=ff
where you make the '03:00.0' match whatever the address for your video card is showing in lspci.
ff in the above command will try to open the latency all the way up to max burst size and max getting along better with others (might help)
you can also try other numbers including lower ones than defaults.. some video drivers might not take this command at all.
also might help to make sure mtrr is being set on your video memory
i have to use the command
echo "base=0xc0000000 size=0x10000000 type=write-combining" >| /proc/mtrr
at boot but i can remember the procedure for comming up with the proper command.
just google mtrr.

last but not least is to recompile the kernel with it set to use a better scheduling algorithm.

I checked if DMA was enabled using "cat /proc/ide/hda/settings" and using_dma is set to 0 so attempting to follow a tutorial I found I installed hdparm and this is the results of what happens when I try to enable DMA.

root@cegan-lfs:/home/chris$ hdparm -i /dev/hda

/dev/hda:

Model=FUJITSU MHV2080AT PL, FwRev=008300A1, SerialNo=NS90T642CYCE
Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs }
RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=0
BuffType=DualPortCache, BuffSize=8192kB, MaxMultSect=16, MultSect=16
CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=156301488
IORDY=yes, tPIO={min:240,w/IORDY:120}, tDMA={min:120,rec:120}
PIO modes: pio0 pio1 pio2 pio3 pio4
DMA modes: mdma0 mdma1 mdma2
UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5
AdvancedPM=yes: mode=0x80 (128) WriteCache=enabled
Drive conforms to: unknown: ATA/ATAPI-2,3,4,5,6,7

* signifies the current active mode

root@cegan-lfs:/home/chris$ hdparm -d1 /dev/hda

/dev/hda:
setting using_dma to 1 (on)
HDIO_SET_DMA failed: Operation not permitted
using_dma = 0 (off)
root@cegan-lfs:/home/chris$

It says "HDIO_SET_DMA failed: Operation not permitted" but I don't understand this. As you can see by my prompt I am logged in as root.
The guide I attempted to follow is http://www.linuxjournal.com/article/5203

Thanks for your advice studioj!
If anyone knows why i'm getting this Operation not permitted please let me know!!

I found the solution and everything seems to be working now!!! Thanks so much! If anyone comes across this same problem looking at this thread in the future I found the answer in another thread http://www.linuxquestions.org/questi...d.php?t=260894


I recompiled my kernel and it worked like a charm