Newsgroups: php.internals Path: news.php.net Xref: news.php.net php.internals:31038 Return-Path: Mailing-List: contact internals-help@lists.php.net; run by ezmlm Delivered-To: mailing list internals@lists.php.net Received: (qmail 9321 invoked by uid 1010); 18 Jul 2007 08:23:43 -0000 Delivered-To: ezmlm-scan-internals@lists.php.net Delivered-To: ezmlm-internals@lists.php.net Received: (qmail 9289 invoked from network); 18 Jul 2007 08:23:42 -0000 Received: from unknown (HELO lists.php.net) (127.0.0.1) by localhost with SMTP; 18 Jul 2007 08:23:42 -0000 Authentication-Results: pb1.pair.com header.from=derick@php.net; sender-id=unknown Authentication-Results: pb1.pair.com smtp.mail=derick@php.net; spf=unknown; sender-id=unknown Received-SPF: unknown (pb1.pair.com: domain php.net does not designate 82.94.239.5 as permitted sender) X-PHP-List-Original-Sender: derick@php.net X-Host-Fingerprint: 82.94.239.5 jdi.jdi-ict.nl Linux 2.6 Received: from [82.94.239.5] ([82.94.239.5:45918] helo=jdi.jdi-ict.nl) by pb1.pair.com (ecelerity 2.1.1.9-wez r(12769M)) with ESMTP id 94/F2-18661-D0ECD964 for ; Wed, 18 Jul 2007 04:23:42 -0400 Received: from localhost (localhost [127.0.0.1]) by jdi.jdi-ict.nl (8.13.7/8.12.11) with ESMTP id l6I8NYS9007090; Wed, 18 Jul 2007 10:23:34 +0200 Date: Wed, 18 Jul 2007 10:23:34 +0200 (CEST) X-X-Sender: derick@kossu.ez.no To: Rasmus Lerdorf cc: David Wang , internals@lists.php.net In-Reply-To: <46990E11.8090209@lerdorf.com> Message-ID: References: <0E6F6F20-5F50-4FC0-9B24-F960A36E0C80@procata.com> <46990E11.8090209@lerdorf.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=UTF-8 Subject: Re: [PHP-DEV] Mid-term Update for Cycle Collector (Google Summer of Code Project) From: derick@php.net (Derick Rethans) On Sat, 14 Jul 2007, Rasmus Lerdorf wrote: > David Wang wrote: > >> Is it possible that total server throughput with gc could actually be > >> better than unmodified php by preventing swapping at some higher > >> level of concurrent requests? > > > > Yes, that's certainly true if it becomes the case that concurrent > > requests take up so much memory that they induce swapping! If that > > ever happens, the system will basically come to a complete standstill. > > No matter what the GC does, it still will be effectively infinitely > > faster than saving and retrieving information from the hard drive. > > It is still extremely rare for code to have cyclic references. So while > GC could prevent swapping in the case of a malicious user, or in the > case of a coding mistake, I don't think the general case of typical code > running under normal circumstances would consume less memory with GC > enabled. It all depends on the code of course - things that do parsing usually tend to have cyclic structures (to keep a link to the "parent"). Derick -- Derick Rethans http://derickrethans.nl | http://ez.no | http://xdebug.org