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Date: Wed, 03 Nov 2010 09:32:45 +0000
From: David Xu <davidxu@freebsd.org>
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To: Julian Elischer <julian@freebsd.org>
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Cc: freebsd-threads@freebsd.org
Subject: Re: Thread ID is reused too quickly
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Julian Elischer wrote:
> On 11/2/10 9:38 AM, David Xu wrote:
>> Our kernel thread ID is reused too quickly, is there any way to fix it ?
> 
> we could free them into a holding pool, (an array set up as a ring buffer)
> with (say) several hundred slots..
> until the pool fills up we don't actually give any thread-IDs back and 
> when it fills
> up we put the ID we are removing into the head of the queue and give 
> back the
> one that is at the other end of the queue.
> 
> I think it would be very easy to implement.. you might even have a 
> per-cpu version
> if you didn't want a lock or maybe there is a lock already in use we can 
> hide it under.
> 
> 
> Julian

Yes, we use the ring buffer in thread library to delay a thread
structure to be reused too quickly, I agree that kernel can do the same
thing.  :-)