On my system (RedHat 9):
$ cat /proc/version
Linux version 2.4.20-8 ([EMAIL PROTECTED]) (gcc version
3.2.2 20030222 (Red Hat Linux 3.2.2-5)) #1 Thu Mar 13 17:54:28 EST
2003
# hdparm -d /dev/hda
/dev/hda:
using_dma = 1 (on)
When I did ``cat /dev/zero > junk``, the system did become
half-irresponsive (not critically). Since DMA is already on, is there
any point in upgrading the kernel?
Another question: "fork bomb"s. I think this was much worse a few
years ago but still, when I do::
perl -e 'for $i (1..15) { fork(); }'
the system gets completely stuck for a few seconds. Increasing the
number increases the stuck time. Isn't a unix suppossed to protect
users from such DOS attacks in some way (just checked, executing it
from another user has exactly the same effect)?
Perhaps it does: curiously enough, after doing this a dozen times, it
seems that linux has "learnt" the trick: I can now fork 2^20 times
with no effect! Can someone enlighten me what goes on?
--
Beni Cherniavsky <[EMAIL PROTECTED]>
=================================================================
To unsubscribe, send mail to [EMAIL PROTECTED] with
the word "unsubscribe" in the message body, e.g., run the command
echo unsubscribe | mail [EMAIL PROTECTED]
