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<== Date ==> <== Thread ==>

Subject: Re: enhanced seq record
From: Benjamin Franksen <benjamin.franksen@bessy.de>
To: core-talk@aps.anl.gov
Cc: tech-talk@aps.anl.gov
Date: Sat, 28 Jan 2006 01:22:36 +0100
On Saturday 28 January 2006 00:52, Chestnut, Ronald P. wrote:
> If you do change the seq record (or make a new one), can you please
> change the behaviour for a "0" delay? Now a new thread is started for
> each (DOL/LNK) pair. If the delay is zero, can you "just do it" in
> the same thread? We found that for some big "explosions" (nested
> SEQs) the task switching dominates the processing time.

I am quite sure the seq record, as it stands, does not start a new 
thread for each link group (=DOL/LNK pair). In R3.13 it uses a watchdog 
timer to request a callback and in R3.14 it uses callbackRequestDelayed 
(which probably is implemented using such a timer; I didn't look at the 
sources).

However, it /does/ request a callback for each group, regardless whether 
the delay is zero or not, and this can indeed cause unnecessary context 
switches. So, yes, I will change this. Adjacent link groups with zero 
delay will be processed in a synchronous manner i.e. w/o requesting a 
callback.

Thanks for the hint.

Cheers,
Ben

Replies:
Re: enhanced seq record Luedeke Andreas
References:
RE: enhanced seq record Chestnut, Ronald P.

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