David Z Maze wrote:
This is with my Dell Latitude C600. Somewhat recently, I've noticed that, when there's heavy disk activity, the entire system grinds almost to a halt. I suspect I've noticed it more since I've installed postgresql and imported a reasonably large data set into it; running VACUUM FULL ANALYZE over the database will kill the system. The daily updatedb process also hurts a lot.The symptom is just that everything is reeeallly slloooowwwww... playing Vorbis files under xmms breaks a lot, the mouse is unresponsive and jerky, and so on. If I watch what's going on using, say, mgm, there's somewhat minimal disk traffic (perhaps 4-8k sectors/second read, peaks up to 32k sectors) and basically no CPU cycles being used. Poking with top suggests that both postmaster (the postgresql server) and kjournald are blocking; is ext3fs hurting me unnecessarily here? AFAIK I've set up everything that wants to be with hdparm, including IRQ unmasking, 32-bit I/O, and DMA. There's no particular hints in the system logs that anything is amiss ("PIIX4: not 100% native mode: will probe irqs later", but this doesn't sound like the end of the world). Any hints?
I experienced the same problem on my Dell I8100. I now use kernel 2.4.20 with O(1) scheduler, preemptible, low latency patches available on Con Kolivas Kernel patch homepage (http://members.optusnet.com.au/ckolivas/kernel/). I also added 'noatime' to /etc/fstab (in the mount man page it seemed not that useful to me). "/dev/hda4 / ext3 defaults,noatime,errors=remount-ro 0 1". Since then xmms plays always smoothly during long find processes :-) -- DoM
