From owner-freebsd-current Mon Apr 20 23:00:42 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id XAA04317 for freebsd-current-outgoing; Mon, 20 Apr 1998 23:00:42 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from ren.dtir.qld.gov.au (firewall-user@ns.dtir.qld.gov.au [203.108.138.66]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id GAA04310 for ; Tue, 21 Apr 1998 06:00:35 GMT (envelope-from syssgm@dtir.qld.gov.au) Received: by ren.dtir.qld.gov.au; id QAA05681; Tue, 21 Apr 1998 16:00:05 +1000 (EST) Received: from ogre.dtir.qld.gov.au(167.123.8.3) by ren.dtir.qld.gov.au via smap (3.2) id xma005661; Tue, 21 Apr 98 15:59:52 +1000 Received: from troll.dtir.qld.gov.au (troll.dtir.qld.gov.au [167.123.8.1]) by ogre.dtir.qld.gov.au (8.8.7/8.8.7) with ESMTP id PAA08300 for ; Tue, 21 Apr 1998 15:59:51 +1000 (EST) Received: from localhost (syssgm@localhost) by troll.dtir.qld.gov.au (8.8.5/8.8.5) with SMTP id PAA09123; Tue, 21 Apr 1998 15:59:48 +1000 (EST) Message-Id: <199804210559.PAA09123@troll.dtir.qld.gov.au> X-Authentication-Warning: troll.dtir.qld.gov.au: syssgm@localhost didn't use HELO protocol To: freebsd-current@FreeBSD.ORG cc: syssgm@dtir.qld.gov.au Subject: NFS corruption Date: Tue, 21 Apr 1998 15:59:47 +1000 From: Stephen McKay Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG NFS is eating my .depend files during a make world. The client is a Compaq Prolinea 486SX33 with 12Mb ram and 2 small SCSI-1 disks on an Adaptec 1542b. The server is a pentium 133 with 32Mb ram and 2 4Gb IBM UW SCSI disks on a FirePort 40 (ncr 875). The source and objects are on the server and NFS mounted to the client. The client mounts src readonly and obj read-write (and async, if that does anything under NFS). The client kernel (and userland) is -current from April 19 (April 18 US time), and has DIAGNOSTIC set. The server is -current from March 12, just before the big VM changes. Memory is short on the client, so paging is brisk. There is plenty of swap space free. I don't run CAM or softupdates. I ran 'make -j2 buildworld' and several hours later observed unusual error messages complaining about garbage in .depend files. Many .depend files were affected. Each .depend file was broken similarly. They would start normally, then the corruption would start on a page boundary (multiple of 0x1000), but *not* extend as far as the next page boundary. The corruption was either C source, or C preprocessor output overwriting the normal contents. >From this evidence I suspect bugs when handling partial page writes, either in NFS or the general VM system. I can't be sure whether the client or the server is at fault. Unfortunately, this is a pretty vague diagnosis. Fortunately, this is now a permanent setup at my place, so I can run tests until my power bill bankrupts me! So, any ideas on how I should tackle this? Stephen. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message