On Thu, 2005-03-24 at 14:11 -0600, Aleksandar Milivojevic wrote: > William Hooper wrote: > > Ow Mun Heng said: > > [snip] > > > >>The author then compares the results with that of BSD eg: OpenBSD and > >>FreeBSD IIRC, and notes that on a system with Pentium 90 w/ 32MB Ram, on > >>using the forkbomb, doesn't bring the system down to it's knees. > > > > > > Following the discussion on the -devel list, the BSDs aren't immune. > > > > https://www.redhat.com/archives/fedora-devel-list/2005-March/msg01201.html > > I gave a try to "while(1) fork();" on OpenBSD (SS5, 64MB RAM). You > can't go much simpler than that. Results: > > Running as normal user, max number of processes is limited to 64 by > default, load average went to 50-something. Perfectly able to kill > offending process(es). > > Running as root, max number of processes is limited to 340, load average > went to almost 300. Not able to do much, since root couldn't create any > new processes (in order to kill existing), but top worked, and already > running processes worked. Anyhow, if somebody does fork bomb as root, > he could just as well type "halt" or wipe out the disk or do some other > irreversable damage. > > The maximum number of processes per user is hard coded in OpenBSD > kernel. It is 340 for root, and 64/128 for normal users in my generic > kernel (soft limit is 64, hard limit is 128). If you want more either > for root or normal users, you need to recompile the kernel. In *BSD > world, recompiling the kernel is something you do twice a day anyhow, so > this isn't much of a problem ;-) > > For those interested, these are ulimits on stock OpenBSD (user and root, > soft and hard). > [SNIP] I see.. So, ulimits _are_ set by default(lower) in *BSDs and not as what I thought that they had some kind of process watchdog in place. Thanks for clearing that up. -- Ow Mun Heng Gentoo/Linux on DELL D600 1.4Ghz 98% Microsoft(tm) Free!! Neuromancer 10:18:48 up 1 day, 56 min, 5 users, load average: 0.41, 0.41, 0.51
