Re: Ups 3.37-bet4 taking larges amounts of CPU time

From: Tom Hughes (thh_at_cyberscience.com)
Date: Wed Jan 09 2002 - 10:33:17 GMT


In message <3C3C16F4.8B8CE156_at_ccieurope.com>
        Flemming Madsen <fma_at_ccieurope.com> wrote:

> I have always wondered why Ups would take up all CPU on linux
> while the target is running.  In my experience that _is_ happening.

It was only taking around 20-30% on my machine, but it is a dual 1.33GHz
Athlon and slower systems might see somewhat higher utilisation.

> Why not usleep() for maybe 10ms for each iteration. That would most
> probably take the CPU load down to a sub-percent level.

I had considered that actually ;-) It is a bit hacky, but it does
indeed seem to have the desired effect. Here's a patch for anyone
that wants to try it:

--- ups-3.37-beta4/ups/ao_ptrace.c.orig	Wed Jan  9 10:30:00 2002
+++ ups-3.37-beta4/ups/ao_ptrace.c	Wed Jan  9 10:30:10 2002
@@ -257,6 +257,7 @@
 					want_timer = 0;
 				}
 			}
+			usleep(10);
 			continue;
 		}
 		else if (user_wants_stop(FALSE)) /* RGA so Stop button breaks */

Tom

-- 
Tom Hughes (thh_at_cyberscience.com)
Software Engineer, Cyberscience Corporation
http://www.cyberscience.com/


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