Hi, I have a P4 at work, and I have been having bad times trying to make it work with hyper-threading enabled. What happens are occasional lockups -- system appears to hang (keyboard, mouse and X freeze, although machine still responds to pings; all other services -- ssh, web, postgres -- are also dead). Last time it froze, its last words were: May 19 14:11:19 dali kernel: APIC error on CPU1: 00(40) May 19 14:11:39 dali kernel: hda: dma_timer_expiry: dma status == 0x24 I know about APIC problems, but the fact is that if I pass 'noapic' to the kernel before boot, the sibling CPU is detected but it doesn't seem to be activated: it appears on top and gkrellm but it never does anything (i.e. it remains with 0% usage). I googled around, and this dma_timer_expiry problem seems to be kernel 2.6.x related. This leads me to think this is specific to Fedora kernel, since RH backported many 2.6 features into its 2.4 kernel... I am compiling a vanilla kernel as we speak, will try it out during the weekend. However, given the fact that Fedora kernel is supposed to provide superior performance compared to vanilla kernels, I would like to use it instead, if at all possible... So, my questions are: 1. any success stories out there about SMP + Fedora on P4s? 2. any black-magic to use besides 'noapic', 'acpi=ht' and 'apm=off'? 3. do vanilla kernels work with Fedora just fine (w/ or w/o SMP)? BTW: FC2 is not an option in the near future, so please don't suggest I upgrade ;) TIA Andre -- Andre Oliveira da Costa
