Running here SMP dual celeron, 440BX, 2HD( Maxtor 1G IBM 9G) ISA 3c509, 128MB ram, nfsroot server for 2 clients, X, workstation, Once a day of serious usage computer locks up. Most part sysrq works. Now I had to work on text-console(test9 clean) for some days and got 2 lockups: 1. nfs was in D state if I remember correctly (or R)(sysrq works) but userland is stuck. 2. httpd(not livin on nfs) stop caused then cpu1 to detect lockup (and sysrq didnt work) httpd stop is a weird operation, on some computers with e2compr this caused a logmessage about async io. logs show nothing. It has been so for whole 2.4.0-test[5-9] time(I did not try earlier much, 2.3.99-pre6 was latest, nfs activity seems to be most guilty, however, I can not see any way to debug it when it happens under X. Anyway, the complaining about SMP instablity seems very justified, because, I had to pump 1GB of logs into mysql and 2.2.18-pre9 did the job, so it is very probably not a hardware problem. 2.2.18-pre9 is up and running for 35 hours now, incuding 10 hours mysql with loadavg 3. nfsroot clients are 2.2 and 2.4. If anyone wants me to do some setup-specific stresstests, u are welcome. elmer. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/