From: tmoran@acm.org
Subject: Re: task-safe hash table?
Date: Sat, 03 Jun 2006 15:40:52 -0500
Date: 2006-06-03T15:40:52-05:00 [thread overview]
Message-ID: <9ZudndYoBv9JbhzZRVn-ig@comcast.com> (raw)
In-Reply-To: u5CdnZhDM4LUrBzZnZ2dnUVZ_vGdnZ2d@comcast.com
> >What about a window in which each task makes, say, n searches. n is the
> >window size. All misses are postponed till the window end. At that point
> ...
> Perhaps a windowing or batching approach such as you suggest would
> distribute the Protected overhead over more useful work and make the
> concurrent approach faster. I'll look into that this weekend.
Dual tasking takes 2/3 as long as sequential.
The k-nucleotide strings start half the time with 'A' or 'C' and half
the time with 'G' or 'T'. So I tried using one hash table for the former
and one for the latter. Then there is no synchronization needed (till
printing the results). Running with the main program handling A+C and a
second task concurrently handling G+T drives CPU usage up to 96% and takes
2/3 the wall clock time, as compared to doing A+C followed sequentially by
G+T (which only takes CPU usage up to 50%, or all of one core on this
dual-core Pentium).
So Ada multitasking on a multi-core CPU gives substantial improvements
for another of the shootout benchmarks (which I believe, unfortunately,
are officially measured on obsolete single-core CPUs).
next prev parent reply other threads:[~2006-06-03 20:40 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-05-29 21:42 task-safe hash table? tmoran
2006-05-29 22:56 ` John
2006-05-30 0:18 ` tmoran
2006-05-30 3:50 ` John
2006-05-30 4:35 ` tmoran
2006-05-30 9:50 ` Georg Bauhaus
2006-06-01 6:32 ` Simon Wright
2006-06-01 19:30 ` tmoran
2006-06-01 20:03 ` Ludovic Brenta
2006-06-01 20:07 ` Dmitry A. Kazakov
2006-06-02 4:31 ` Jeffrey R. Carter
2006-06-02 10:36 ` Stephen Leake
2006-06-03 6:50 ` tmoran
2006-06-03 20:40 ` tmoran [this message]
2006-06-02 10:35 ` Stephen Leake
2006-06-02 20:19 ` tmoran
2006-06-03 21:10 ` M E Leypold
2006-06-04 0:23 ` tmoran
2006-06-04 12:55 ` Stephen Leake
2006-06-04 17:22 ` tmoran
2006-06-08 1:10 ` Stephen Leake
2006-06-11 13:29 ` Georg Bauhaus
2006-06-04 17:48 ` Simon Wright
2006-06-05 0:23 ` tmoran
2006-06-05 21:57 ` Steve Whalen
2006-06-06 11:10 ` Ole-Hjalmar Kristensen
2006-05-30 15:00 ` Matthew Heaney
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