There's a classic Unix problem with distribution of disk access times that relates to how older Unixes did "sync" -- every 30 seconds there was an instant traffic jam at the interface to the drives. This has been studied to death; here are some assorted papers:
http://www.cis.upenn.edu/~jms/usenix.pdf Has graphs from old DEC hardware that look similar to XO-1.5. http://www.usenix.org/events/osdi06/tech/nightingale/nightingale.pdf Good references section. http://www.eecs.umich.edu/Rio/papers/chen96_2.pdf Studies ext3 performance in depth. Most such studies looked at read() times because the usual workload has far more reads than writes. Odd delays in write() times are interesting. John _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
