Is the operation IndexSearcher.search I/O or CPU bound if I am doing 100's of searches on the same query?
Thanks -John On Thu, 06 Jan 2005 10:31:49 -0800, Doug Cutting <[EMAIL PROTECTED]> wrote: > John Wang wrote: > > 1 thread: 445 ms. > > 2 threads: 870 ms. > > 5 threads: 2200 ms. > > > > Pretty much the same numbers you'd get if you are running them sequentially. > > > > Any ideas? Am I doing something wrong? > > If you're performing compute-bound work on a single-processor machine > then threading should give you no better performance than sequential, > perhaps a bit worse. If you're performing io-bound work on a > single-disk machine then threading should again provide no improvement. > If the task is evenly compute and i/o bound then you could achieve at > best a 2x speedup on a single CPU system with a single disk. > > If you're compute-bound on an N-CPU system then threading should > optimally be able to provide a factor of N speedup. > > Java's scheduling of compute-bound theads when no threads call > Thread.sleep() can also be very unfair. > > Doug > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
