X-Recipient:	archive-cygwin AT delorie DOT com
X-Spam-Check-By:	sourceware.org
Date:	Wed, 1 Sep 2010 15:10:32 -0400
From:	Christopher Faylor <cgf-use-the-mailinglist-please AT cygwin DOT com>
To:	cygwin AT cygwin DOT com
Subject:	Re: Cygwin slow on x64 systems
Message-ID:	<20100901191031.GE15157@ednor.casa.cgf.cx>
Reply-To:	cygwin AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
References:	<4C7B9327 DOT 9030204 AT graphtech DOT co DOT il>
MIME-Version:	1.0
In-Reply-To:	<4C7B9327.9030204@graphtech.co.il>
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 Mon, Aug 30, 2010 at 02:16:55PM +0300, Sagi Ben-Akiva wrote:
>For the last couple of weeks I'm trying to identify the cause for cygwin 
>slowdown on x64 machines which was reported by David Morgan about 6 
>months ago.
>
>Using cvsps I was able to generate a patchset which contains all the 
>changes between those 2 revisions.
>I then applied the changes one by one and built cygwin1.dll for each 
>change, then I ran my test script again for each cygwin1.dll version and 
>I found that the change to winsup/cygwin/dcrt0.cc from '2006/03/12 
>23:57:03' introduce this issue.
>
>The log for this change is :
>
>* dcrt0.cc (dll_crt0_0): Call sigproc_init during init startup.
>(_dll_crt0): Don't worry about sync_startup.  Just wait for sigthread here.
>
>This change includes 2 different sub-changes :
>1. Moving the call to sigproc_init from dll_crt0_1 function to 
>dll_crt0_0 - which doesn't affect performance.
>
>2. a. Moving the call to wait_for_sigthread from dll_crt0_1 to _dll_crt0 
>which calls dll_crt0_1.
>    b. Deleting the call to WaitForSingleObject,
>       i.e. : "Don't worry about sync_startup"
>
>I can confirm that the 2nd sub-change is the cause for the slowdown.
>
>Any help will be appreciated.

I rewrote the signal initialization stuff today and have generated a
new snapshot.  Please let me know if this works better for you.  I haven't
actually tried to run a fork per sec.  test yet so there may be other
lurking problems.

http://cygwin.com/snapshots/

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 -