X-Recipient:	archive-cygwin AT delorie DOT com
X-Spam-Check-By:	sourceware.org
Date:	Fri, 20 Nov 2009 09:38:33 -0500
From:	Christopher Faylor <cgf-use-the-mailinglist-please AT cygwin DOT com>
To:	cygwin AT cygwin DOT com
Subject:	Re: 1.5.25-15: pthread_join deadlocks
Message-ID:	<20091120143833.GE18289@ednor.casa.cgf.cx>
Reply-To:	cygwin AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
References:	<20091119124405 DOT GF29173 AT calimero DOT vinschen DOT de> <4B067444 DOT 80900 AT ece DOT cmu DOT edu> <4B06A11C DOT 6030101 AT cwilson DOT fastmail DOT fm>
MIME-Version:	1.0
In-Reply-To:	<4B06A11C.6030101@cwilson.fastmail.fm>
User-Agent:	Mutt/1.5.20 (2009-06-14)
Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id:	<cygwin.cygwin.com>
List-Unsubscribe:	<mailto:cygwin-unsubscribe-archive-cygwin=delorie DOT com AT cygwin DOT com>
List-Subscribe:	<mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive:	<http://sourceware.org/ml/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender:	cygwin-owner AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
Delivered-To:	mailing list cygwin AT cygwin DOT com

On Fri, Nov 20, 2009 at 09:01:00AM -0500, Charles Wilson wrote:
>Ryan Johnson wrote:
>> Out of curiosity, how much did removing the racy optimization hurt
>> performance? The patch just yanked it completely iirc. An alternative
>> might be to have the main thread check for single-thread environment
>> only at acquire time, and then release only if it acquired (the latter
>> is probably a good idea regardles...).
>
>The problem is, IIRC there is no such thing as a single-thread
>environment for cygwin programs: every cygwin program has a secondary
>thread that handles translating certain windows events into unixy
>signals, or something like that. I think.

Yes, there's at least one extra thread active in every cygwin program.
If you've used select() at any point there will be more.

cgf

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

- Raw text -