From owner-freebsd-current@FreeBSD.ORG Tue Mar 30 08:58:48 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C19E516A4CE for ; Tue, 30 Mar 2004 08:58:48 -0800 (PST) Received: from smtp.des.no (flood.des.no [217.116.83.31]) by mx1.FreeBSD.org (Postfix) with ESMTP id 79EAF43D2F for ; Tue, 30 Mar 2004 08:58:48 -0800 (PST) (envelope-from des@des.no) Received: by smtp.des.no (Pony Express, from userid 666) id 3A08D5309; Tue, 30 Mar 2004 18:58:47 +0200 (CEST) Received: from dwp.des.no (des.no [80.203.228.37]) by smtp.des.no (Pony Express) with ESMTP id 2914E5308 for ; Tue, 30 Mar 2004 18:58:29 +0200 (CEST) Received: by dwp.des.no (Postfix, from userid 2602) id 092DF33CAA; Tue, 30 Mar 2004 18:58:29 +0200 (CEST) To: current@freebsd.org From: des@des.no (Dag-Erling =?iso-8859-1?q?Sm=F8rgrav?=) Date: Tue, 30 Mar 2004 18:58:28 +0200 Message-ID: User-Agent: Gnus/5.090024 (Oort Gnus v0.24) Emacs/21.3 (berkeley-unix) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on flood.des.no X-Spam-Level: X-Spam-Status: No, hits=0.0 required=5.0 tests=AWL autolearn=no version=2.63 Subject: performance of jailed processes X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 30 Mar 2004 16:58:48 -0000 Can anyone explain why jailed processes seem to perform much worse than non-jailed processes in recent -CURRENT? Specifically, running a query against a remote MySQL server from inside a jail takes an order of magnitude more time than from outside the jail. Tcpdump shows that the TCP packets carrying the result are evenly spaced, so this is not a matter of the server timing out on a DNS lookup or anything like that. Running a configure script also takes much longer inside the jail than outisde, and again, progress is even (though slow), so it is clearly not a matter of DNS timing out. There is no NFS or NIS in the equation either. Parts of the file space inside the jail is a nullfs mount, but we've also tried without nullfs. The system currently uses SCHED_ULE, but we had similar trouble with SCHED_4BSD on 5.1-RELEASE before we went -CURRENT. The machine currently has ~2600 processes running in ~400 jails. Is it conceivable that be scalability issues, perhaps in the credentials code, could cause vastly increased syscall overhead for jailed processes? DES --=20 Dag-Erling Sm=C3=B8rgrav - des@des.no