From owner-freebsd-hackers@FreeBSD.ORG Thu Mar 27 01:45:52 2003 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id BB62837B401 for ; Thu, 27 Mar 2003 01:45:52 -0800 (PST) Received: from park.rambler.ru (park.rambler.ru [81.19.64.101]) by mx1.FreeBSD.org (Postfix) with ESMTP id 02C7543FA3 for ; Thu, 27 Mar 2003 01:45:49 -0800 (PST) (envelope-from is@rambler-co.ru) Received: from is.park.rambler.ru (is.park.rambler.ru [81.19.64.102]) by park.rambler.ru (8.12.6/8.12.6) with ESMTP id h2R9jfmF091067; Thu, 27 Mar 2003 12:45:41 +0300 (MSK) Date: Thu, 27 Mar 2003 12:45:41 +0300 (MSK) From: Igor Sysoev X-Sender: is@is To: freebsd-hackers@FreeBSD.ORG In-Reply-To: <3E8163C5.3024.3C0A1A9@localhost> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Spam-Status: No, hits=-25.5 required=5.0 tests=AWL,EMAIL_ATTRIBUTION,IN_REP_TO,QUOTED_EMAIL_TEXT, REPLY_WITH_QUOTES,USER_AGENT_PINE autolearn=ham version=2.50 X-Spam-Level: X-Spam-Checker-Version: SpamAssassin 2.50 (1.173-2003-02-20-exp) Subject: Re: shared mem and panics when out of PV Entries X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 27 Mar 2003 09:45:55 -0000 On Wed, 26 Mar 2003, Andrew Kinney wrote: > Eventually, I may be forced to turn off KeepAlive and make use of If you disable keepalive I believe clients would not see much difference. Keepalive is a good feature for clients but it should be enabled if you have enough resources to support it. It can be enabled on light-weight server that uses kqueue and designed to handle the tens of thousands simultaneous connections. An overhead per connection would be several tens of kilobytes or less. A plain Apache without heavy modules spends hunderds of kilobytes of physical memory per connection. mod_perl spends megabytes or tens of megabytes of phycical memory per connection. In your untypical case Apache spends about 1.5M per connection of a kernel memory. > FreeBSD's accept filters My measurements on the loaded enough web sites show that the accept filters allow to save about 5-10% of Apaches. Of course they are the most effective without keepalives. But be sure use them only in between 4.1.1-RELEASE - 4.4-RELEASE, or 4.6-RELEASE and above. 4.5-RELEASE and -STABLE around have the syncache related bug that leads to DoS. > or put in a reverse proxy as you recommend. I can even recommend you one proxy - mod_accel - http://sysoev.ru/en/ > For now, though, we are serving the whole gammut > from this Apache. Static pages, images, mod_perl, PHP, > Apache::ASP, and most anything else a customer might want or > need to serve from a web server. I know it isn't the most efficient > way to use Apache, but nobody has any complaints about > performance at this point. You have too much overhead per connection and if the worload would grow you will have perfomance problems. Igor Sysoev http://sysoev.ru/en/