X-Recipient: archive-cygwin AT delorie DOT com
DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:subject:to:references:from:message-id:date
	:mime-version:in-reply-to:content-type
	:content-transfer-encoding; q=dns; s=default; b=lvs0WOsESw8Ukvkg
	4FZwnm9L5QrDQdbHL7BreRQFlqYP1FEuoqncpqU7PwNWwm8OIV7cmmOK3XrQdUo/
	77Ue5L3WsqjFmYvwxGaLX43WXLSYy676mXPReaPj0D8D267aVdVelcrsa5YFYYsD
	6bQM4wQMAT9zDa3NetuJPdM77S4=
DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id
	:list-unsubscribe:list-subscribe:list-archive:list-post
	:list-help:sender:subject:to:references:from:message-id:date
	:mime-version:in-reply-to:content-type
	:content-transfer-encoding; s=default; bh=+VrL9gGhLtkykmOIVMLylH
	mHx1o=; b=Irf9iRhHPxcnm8nhQcrbnPSKPh96sU+ZgCw/8zU6v263X3jo2EzcJT
	ZW/cVKcRKfcHmzJF0Lh84sFd9DhC4QlMLuoOzrSHrzDH9ubASXUcmnp4YA5JRKb3
	A1N7KjygSPks9spTgm7PkM0tJ+SlQRjQTt/i97CLGzl5b7b9YHK5w=
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id: <cygwin.cygwin.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
Authentication-Results: sourceware.org; auth=none
X-Virus-Found: No
X-Spam-SWARE-Status: No, score=-2.7 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 spammy=gluszczak, Gluszczak, Glenn, services
X-HELO: sasl.smtp.pobox.com
Subject: Re: long I/O delays when strace is running
To: cygwin AT cygwin DOT com
References: <be8713ec-5b68-e0e9-c5a5-d48fce491a2d AT pobox DOT com> <91DCAC3CB99C724EB365BB64677FBE7B16EBBD AT MX204CL04 DOT corp DOT emc DOT com>
From: Daniel Santos <daniel DOT santos AT pobox DOT com>
Message-ID: <46e39bce-9782-5c74-c196-35ee97ebbc64@pobox.com>
Date: Thu, 20 Apr 2017 21:38:41 -0500
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1
MIME-Version: 1.0
In-Reply-To: <91DCAC3CB99C724EB365BB64677FBE7B16EBBD@MX204CL04.corp.emc.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
X-Pobox-Relay-ID: FBD9D510-263A-11E7-BE56-E680B56B9B0B-06139138!pb-smtp1.pobox.com
X-IsSubscribed: yes

On 04/20/2017 08:43 AM, Gluszczak, Glenn wrote:
> I haven't run Cygwin Expect for about 6 moths on Windows but it was behaving fine last time I did.
> One thing I am aware of is you can't interrupt sleep in TCL.  The sleep must
> complete until the Control C is processed (regardless of whether you redirected signals
> to your own routines).  Otherwise signals seemed to be processed immediately.

Please note that my simplified test case isn't using expect, but the 
standard /usr/bin/sleep.exe -- this is just to have strace run and trace 
for a longer amount of time in order to expose the problem. (it did get 
broken into a new line though, so add a backslash:

> for ((i = 0; i < 64; ++i)); do strace --output=/tmp/sleep.$$.log \
> --trace-children --mask=startup sleep 64; done

> Perhaps some other service is interfering.  You may want to disable other services.
>
> Glenn

I usually disable most services, I can probably disable a few more, but 
I would like if somebody can run the above test case in one terminal 
windows and in the other terminal window do a simple ps -ef and let me 
know if ps responds immediately or has a delay.  I am using Windows 7, 
so it could be isolated to that windows version as well.  When I do 
this, ps has a 3 second delay while in 
fhandler_base_overlapped::wait_overlapped, but I've seen this delay in 
other processes while calling something like "open_shared."

Anyway, I'm going to try to find another simple test case that causes 
more of a drastic delay.

Daniel

--
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