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Am 25.09.2015 um 09:32 schrieb Vincent Lefevre: > On 2015-09-24 14:38:01 +0200, Peter Ludikovsky wrote: >> Other than that, what mount command did you use? Are you mounting >> the share yourself, or is this an fstab or autofs mount? > > autofs > > The only option used in /etc/auto.master is the obvious -o nosuid. > > But the options seem to be the same on Debian 7 clients. > >> Do you have any control over the NFS server, and if so what are >> its settings? > > I could ask the admin, if they are useful for the bug. > >> I did manage to replicate your issue. However, it disappears as >> soon as I sync before the mv, as well as when both the rsize and >> wsize parameters are reduced to 65536, suggesting this has >> something to do with a local cache and/or lock. >> >> Apparently the issue also disappears as soon as both sides have >> noac added to the mount options. > > Did you have to change the server settings to replicate the > problem? > > Note that if I do a "touch" on the target before the mv, the > problem doesn't occur. > No, I didn't have to change anything on the server side. noac is a mount setting for NFS, which basically tells the client not to cache any file/directory attributes, but to ask the server each time. My guess is: Due to the rather large wsize/rsize, the clients create a rather large attribute cache. As a result, when you cat a file on the second machine it updates the atime in the cache, but doesn't yet transfer that information to the server. When you do the mv on the first machine, the client tries to get the current attributes on the files involved, which prompts the server to wait until the second client runs into some kind of timeout and updates the attributes. Only then is the second file "unlocked" to be overwritten. Further proof of that: when setting noatime as a mount option, instead of noac, there's also no delay on the mv. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (MingW32) iQIcBAEBAgAGBQJWBQGeAAoJEM+6Ng5pbtyZel8QAItKpN7wTP527aF06YGYymwQ Ema5V6cQ8dfYHT6dr2YKqCdG+I9TZeg4xeX5i6b8jtrbKqTHuOFK95SfN/dt3FTb 6clEgXndEZP022Mko7C7IGVBsQQIgnc57POywsglcBW3Vkq7FhBualg10S+KnhUw XFeHhW9SFNwY6sjM+r77rvzilMjEnbry/ik8gSzEB9Y/Zak92DzHFVB/mQshgZKG uDuwI3ZY9pRsW8QfxfX4/Ueo6IwtrP3K9eBObifbpiuFzfj8h13+hA4rCp+JYfhb +2lvlngzQH6pArk/cXt/7RkIi7Rr4Baxyn4ZR5viO2HcDBtFszsvWJkwHMl6JO5v 7YeNL0ZuVQiHXZ5XjNKiVnMuyu0cBuzgYA/vOqwkMDbJj5GRZ9g2Mu3BIxHjCI5l xqGJ2Lj3RJpzk5K0y0BYurxxEA2Fr4L2r3OqrChHXzYdU/+sCJ1FRvU+tHK++Vdn CgGxnrWn7nzBo3l1MCmj1KeZgEVzCkBJhJ66AWlNL4EUYEDYowolaNOur1dsT9Ci dxYxWru8YyifEW3zNlBkBJXqu4s2YkTY5J7pS4apYX4jvhrKpFkqtlu/gvTYzLrc PU9W/12VsmBQqLhfIo/1We0iRX/wHNyMSHgI/vvWsuwtlgjcM4ECwNK/M96WLncr 0CuIVjGKpxXxn6FOC4Ey =DNAx -----END PGP SIGNATURE-----
