Date: Mon, 22 Mar 2004 12:53:07 -0500 (EST) From: Mike Andrews <mandrews@bit0.com> To: freebsd-stable@lists.freebsd.org Subject: Re: Weird NFSvs rdirplus issues Message-ID: <20040322124916.M59896@mindcrime.bit0.com> In-Reply-To: <20040318144807.E95350@mindcrime.bit0.com> References: <20040318144807.E95350@mindcrime.bit0.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, 18 Mar 2004, Mike Andrews wrote: > The motivating factor in using readdirplus at all is that it drastically > reduces CPU load, ethernet load, and NFS ops/sec on the Netapps, which are > not exactly cheap to upgrade CPU in. When I turned readdirplus off to > stop the file corruption, the Netapp's CPU load pegged at 100% around the > clock. But interestingly, it doesn't seem to raise the actual disk spindle > ops/sec; probably the extra stat() calls are being handled from its disk > cache. Still, the overhead of quadruping the number of NFS calls is too > much for it... Actually, it turns out the load was caused by a client process that got stuck right about the same time I was experimenting with different mount options. Oops. I'm running without rdirplus with normal performance now. Still wish I understood the ac options a bit better though. There's still the issue of mount_nfs dumping core in 4.9 though, if it wasn't already backported from -current to -stable for 4.10... > Bizarre situation #1 is the easy one: when you try to put the acdirmin/max > and acregmin/max options on an NFS filesystem in /etc/fstab, mount > (actually mount_nfs) will dump core on 4.9-RELEASE-p4 but not on > 5.2.1-RELEASE-p3: > > # grep acreg /etc/fstab > server:/fs /mnt nfs,ro,-lis,acdirmin=0,acdirmax=1,acregmin=0,acregmax=1 0 0 > # mount /mnt > mount: server:/fs: Segmentation fault > > (the core file left behind is for mount_nfs, not mount, though) > However running mount_nfs at the command line will work, even on 4.9: > > # mount_nfs -lis -o acdirmin=0,acdirmax=1,acregmin=0,acregmax=1 server:/fs /mnt > > Looks like some kind of parsing error that the fix hasn't been MFC'ed for? > (I haven't been able to check 4.9-STABLE yet to see if the fix made it there.) Mike Andrews * mandrews@bit0.com * http://www.bit0.com "The truth is, you never find the truth." Carpe cavy! It's not news, it's Fark.com.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20040322124916.M59896>