Hello, I'm using Centos 6.4 / 2.6.32-358.6.1.el6.x86_64. Long story short (steps to reproduce with a nfs server on localhost at the end) : I've got an NFS server that share multiple directories. If I mount one directory using -o fsc, everything is fine. If I mount another directory, it also have the fsc option, even if I didn't specify it (and the caching is effective). If I restart from scratch, mount the first directory without the "fsc" option and mount the second directory with the "fsc" option, the second mount does not honor the fsc option : /etc/mtab show the fsc option, but not /proc/mounts. Here is some steps to reproduce the problem on a local machine, without involving a distant NFS server. $ # install necessary package to be a nfs server $ echo "/usr/local/share 127.0.0.1(ro,no_root_squash,no_subtree_check)" | sudo tee -a /etc/exports $ sudo exportfs -a $ sudo mkdir /tmp/mount $ sudo mount -o fsc,vers=3 127.0.0.1:/usr/local/share /tmp/mount # using fsc option ! $ grep /tmp/mount /etc/mtab 127.0.0.1:/usr/local/share /tmp/mount nfs rw,fsc,vers=3,addr=127.0.0.1 0 0 $ grep /tmp/mount /proc/mounts 127.0.0.1:/usr/local/share /tmp/mount nfs rw,relatime,vers=3,rsize=1048576,wsize=1048576,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=127.0.0.1,mountvers=3,mountport=38779,mountproto=udp,fsc,local_lock=none,addr=127.0.0.1 0 0 # FSC OPTION IS PRESENT So far, so good =) Let's try to add a second share : $ echo "/var 127.0.0.1(ro,no_root_squash,no_subtree_check)" | sudo tee -a /etc/exports $ sudo exportfs -a $ sudo mkdir /tmp/mount2 $ sudo mount -o vers=3 127.0.0.1:/var /tmp/mount2 # NOT using fsc option $ grep /tmp/mount2 /etc/mtab 127.0.0.1:/var /tmp/mount2 nfs rw,vers=3,addr=127.0.0.1 0 0 # no fsc option $ grep /tmp/mount2 /proc/mounts 127.0.0.1:/var /tmp/mount2 nfs rw,relatime,vers=3,rsize=1048576,wsize=1048576,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=127.0.0.1,mountvers=3,mountport=38779,mountproto=udp,fsc,local_lock=none,addr=127.0.0.1 0 0 # FSC OPTION IS PRESENT, WEIRD If I reverse the situation (first mount without "fsc", and the second with the "fsc" option), the second mount does not have the fsc option, although I've requested the option. Here is the output of the /proc/fs/nfsfs/volumes in the case of the first mount using the fsc option : $ cat /proc/fs/nfsfs/volumes NV SERVER PORT DEV FSID FSC v3 7f000001 801 0:21 5d0a2a7754517409 yes In the second case (first mount without fsc, and second one with fsc option) : $ cat /proc/fs/nfsfs/volumes NV SERVER PORT DEV FSID FSC v3 7f000001 801 0:20 5d0a2a7754517409 no How should I interpret that ? Is that a limitation I didn't understand in the first place ? Regards, Jean-Baptiste -- Linux-cachefs mailing list Linux-cachefs@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cachefs
