X-Recipient:	archive-cygwin AT delorie DOT com
DKIM-Filter:	OpenDKIM Filter v2.11.0 sourceware.org 00B1A384242C
DKIM-Signature:	v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com;
	s=default; t=1598464651;
	bh=x3qs9bsxld/RaLd8hm7FtOWkA0ISmsqlpIranSJnwNU=;
	h=Date:From:To:Subject:References:In-Reply-To:List-Id:
	List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe:
	Reply-To:From;
	b=NtfgNRHa/8oeDbqCKfyjuO3aZbEFfc0Fo60SGqnqiCTODspB6klSSYsPtxhAiTSfq
	KdDlWliKzf2th9M25YbjOw+nRk+6oXe6gcIGJM8XYq/XWBKvXpZGz4plZ9iDyZ7X+n
	N6l23o1mYS7HfMjajtaRxij9iKGYLvAXbNRNnQyE=
X-Original-To:	cygwin AT cygwin DOT com
Delivered-To:	cygwin AT cygwin DOT com
DMARC-Filter:	OpenDMARC Filter v1.3.2 sourceware.org 1FD733857C47
Authentication-Results:	sourceware.org;
	dmarc=none (p=none dis=none) header.from=cygwin.com
Authentication-Results:	sourceware.org;
	spf=fail smtp.mailfrom=corinna-cygwin AT cygwin DOT com
Date:	Wed, 26 Aug 2020 19:57:24 +0200
From:	Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To:	cygwin AT cygwin DOT com
Subject:	Re: Limit for number of child processes
Message-ID:	<20200826175724.GQ3272@calimero.vinschen.de>
Mail-Followup-To:	cygwin AT cygwin DOT com
References:	<000401d67ba0$8b1f33b0$a15d9b10$@gmail.com>
MIME-Version:	1.0
In-Reply-To:	<000401d67ba0$8b1f33b0$a15d9b10$@gmail.com>
X-Provags-ID:	V03:K1:Hmx8ddgQEfbBCsON+40g66kAVP0cr/zpvIOb3cCJ1S0rO2SLiHf
	GJdU2Zpdh/ygZL3xi8S0w5+QYnbC9Tjheq/8kz8aOxcGpRFWfYUw10Wu9FUauzRYbVqyzg4
	FyYR9dGdzczNUupIfuahbp9K43S7YX9QgefWU34HBltl3ad1fAmE6l9xJipC0Q57yFgZglf
	jhslgq5ODsChZBo4/TJcg==
X-UI-Out-Filterresults:	notjunk:1;V03:K0:BVQVq8xZ7Y0=:L/bxITUNJksTUQT55C/oEp
	vdlhQQYDC5Qv6XfIPt7eIN/xq1BXlqfeBX13clG92e/TWgDIClnUnt5Te+to3Zw9y+dyYaJUp
	4/F6rK8eROaQsI98IFWTRPK+3VzJBX3qEMK3yQoO6Rg7zutmWd6k1gshXkyG+RmLIX31o/xzY
	UpGPV8gOQ1e2t7Xc5Q17kPn8iEAcminUKojWuJvDSwCtcOW+X74fR5sxZ7+DCb6M7izE7owl4
	DIutIg5JPhH2ezQU/QR8N1+eRiCV/khAMXrXdfvUP+XIOCHHD9HBZg4KbXlsNJmCttekYcm/U
	bcX7DPAz3HhgkYPGa+KhZxeuDq38v36mYJopwxYIkgmGFxjdL7IPP8mLqZNlC3aT5DDq3OdKs
	j93hMWzy6D8555C3tFl+v3BKR3NH8ax5R5IbKecNo5aCNHX8B3uEJtZcmQHplwq7yf5wA0GNw
	P7qGNw/Uw3eUzx15VS7rEZ8LzzcIMucJQqP3MJ5piQotrDTrDT3mUWThPnv8Ka9JzXrHpVQKM
	vAZ50XtQfUdmYANhG/eDLZ8SxIdspZolMr692HCROO8h/SPk4djQfS6uWUuGMVypX4sDD8IRq
	0ZwROPHooGpxspZvLo7vXKZcy0BgL3X+z0BlpH8Rw97AYVu8dJK9tIJWjNXexXkmEBx6MvAvE
	A/eKHOadgNai9UaQc5mKb9cZIMwAgwaoZjacJccfFX5vLUyDUDPYx/IeyT8M39oEeG6XJ4WPC
	Q5amrFFJQoWKdKNqNCspkbMwYIVtrJ07KmuDuyDY3xIwCmsXfeytTMXGUHhqwMms8QbFuVHfK
	AvPwsBr16naC+0F8E6ZswOIE9b223bmA97gkLJJ81SImH5kXBo3hP7ntYYUfUxSOrXiqGHz2G
	Fow96TB++OuMclrCgC+g==
X-Spam-Status:	No, score=-99.8 required=5.0 tests=BAYES_00,
	GOOD_FROM_CORINNA_CYGWIN, JMQ_SPF_NEUTRAL, KAM_DMARC_STATUS,
	RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NEUTRAL,
	TXREP autolearn=ham autolearn_force=no version=3.4.2
X-Spam-Checker-Version:	SpamAssassin 3.4.2 (2018-09-13) on
	server2.sourceware.org
X-BeenThere:	cygwin AT cygwin DOT com
X-Mailman-Version:	2.1.29
List-Id:	General Cygwin discussions and problem reports <cygwin.cygwin.com>
List-Unsubscribe:	<https://cygwin.com/mailman/options/cygwin>,
	<mailto:cygwin-request AT cygwin DOT com?subject=unsubscribe>
List-Archive:	<https://cygwin.com/pipermail/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe:	<https://cygwin.com/mailman/listinfo/cygwin>,
	<mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
Reply-To:	cygwin AT cygwin DOT com
Errors-To:	cygwin-bounces AT cygwin DOT com
Sender:	"Cygwin" <cygwin-bounces AT cygwin DOT com>

On Aug 26 14:00, Kristian Ivarsson via Cygwin wrote:
> Dear cygwin folks
> 
> It seems like there's a limit of the number of possible child processes
> defined to 256 with 'NPROCS' in //winsup/cygwin/child_info.h used in
> 'cprocs' in //winsup/cygwin/sigproc.cc
> 
> 256 is quite few possible children in an enterprise environment and perhaps
> the limit should be limited by the physical resources or possibly Windows ?

The info has to be kept available in the process itself so we need
this array of NPROCS * sizeof (pinfo).

Of course, there's no reason to use a static array, the code could just
as well use a dynamically allocated array or a linked list.  It's just
not the way it is right now and would need a patch or rewrite.

As for the static array, sizeof pinfo is 64, so the current size of
the array is just 16K.  We could easily bump it to 64K with NPROCS
raised to 1024 for the next Cygwin release, at least on 64 bit.
I don't think we should raise this limit for 32 bit Cygwin, which is
kind of EOL anyway, given the massive restrictions.


Corinna

-- 
Corinna Vinschen
Cygwin Maintainer
--
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple

- Raw text -