Package: nfs-common Version: 1:1.2.6-3 Severity: normal I believe there is performance degradation in NFS4 client:
sudo mount -t nfs4 debmain:/tmp /mnt/tmp /usr/bin/time -p sh -c 'tree /mnt/tmp | tail -1' 287 directories, 63315 files real 4.22 user 1.32 sys 1.04 When /usr/bin/time -p sh -c 'tree /mnt/tmp | tail -1' is repeated several seconds later the output is this: 287 directories, 63315 files real 24.64 user 1.58 sys 3.42 I tracked it down to "acregmin" NFS mount option: when "acregmin" is over/expired directory walk becomes ~5 times slower in my case. Setting "acregmin=120" on mount will delay the problem for exactly 120 seconds: `tree` will walk directory structure in less than 4 seconds within 2 minutes after first walk, then 120 seconds later it slows down to >24 seconds needed to walk the same tree again. Setting "acregmin=0" makes directory walk time >24 seconds even for the first walk. Cheers, Dmitry Smirnov GPG key : 4096R/53968D1B --- System information. --- Architecture: amd64 Kernel: Linux 3.7-trunk-amd64 --- Package information. --- Depends (Version) | Installed =========================================-+-=================== libc6 (>= 2.3) | 2.13-38 libcap2 (>= 2.10) | 1:2.22-1.2 libcomerr2 (>= 1.01) | 1.42.5-1 libdevmapper1.02.1 (>= 2:1.02.20) | 2:1.02.74-6 libevent-2.0-5 (>= 2.0.10-stable) | 2.0.19-stable-3 libgssglue1 | 0.4-2 libk5crypto3 (>= 1.6.dfsg.2) | 1.10.1+dfsg-4 libkeyutils1 | 1.5.5-3 libkrb5-3 (>= 1.6.dfsg.2) | 1.10.1+dfsg-4 libmount1 (>= 2.19.1) | 2.20.1-5.3 libnfsidmap2 | 0.25-4 libtirpc1 | 0.2.2-5 libwrap0 (>= 7.6-4~) | 7.6.q-24 rpcbind | 0.2.0-8 adduser | 3.113+nmu3 ucf | 3.0025+nmu3 lsb-base (>= 1.3-9ubuntu3) | 4.1+Debian8 initscripts (>= 2.88dsf-13.3) | 2.88dsf-41 libblkid1 (>= 2.16) | 2.20.1-5.3 libc6 (>= 2.3) | 2.13-38 libtirpc1 | 0.2.2-5 libwrap0 (>= 7.6-4~) | 7.6.q-24 nfs-common (= 1:1.2.6-3) | 1:1.2.6-3 ucf | 3.0025+nmu3 lsb-base (>= 1.3-9ubuntu3) | 4.1+Debian8 Recommends (Version) | Installed =========================-+-=========== python | 2.7.3-4 Suggests (Version) | Installed =========================-+-=========== open-iscsi | watchdog | -- /etc/default/nfs-common -- NEED_STATD=no STATDOPTS= NEED_IDMAPD=yes NEED_GSSD= -- /etc/idmapd.conf -- [General] Verbosity = 0 Pipefs-Directory = /var/lib/nfs/rpc_pipefs Domain = local [Mapping] Nobody-User = nobody Nobody-Group = nogroup -- /etc/fstab -- -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/201303071212.08891.only...@member.fsf.org