all file times altered at read/access to file about moosefs HOT 4 CLOSED

@oszafraniec
Hi Oskar,

thanks for your report, we're checking it on our test environment. Could you please provide us with more details about your FreeBSD (FreeBSD version, fusefs-libs version)?

We haven't confirmed this on our test environment so far (moosefs-client 2.0.88, FreeBSD pkonopelko-freebsd10 10.3-RELEASE FreeBSD 10.3-RELEASE #0 r297264: Fri Mar 25 02:10:02 UTC 2016, fusefs-libs-2.9.5 Master and Chunkservers are 3.0.78).

[root@pkonopelko-freebsd10 ~]# echo "asdasdasd" > /mnt/mfs/asd
[root@pkonopelko-freebsd10 ~]# stat /mnt/mfs/asd
3976265474 124 -rw-r--r-- 1 root wheel 0 10 "Jun 20 13:27:16 2016" "Jun 20 13:27:16 2016" "Jun 20 13:27:16 2016" "Jan  1 00:59:59 1970" 4096 1 0 /mnt/mfs/asd
[root@pkonopelko-freebsd10 ~]# cat /mnt/mfs/asd > asd
[root@pkonopelko-freebsd10 ~]# stat /mnt/mfs/asd
3976265474 124 -rw-r--r-- 1 root wheel 0 10 "Jun 20 13:27:44 2016" "Jun 20 13:27:16 2016" "Jun 20 13:27:16 2016" "Jan  1 00:59:59 1970" 4096 1 0 /mnt/mfs/asd
[root@pkonopelko-freebsd10 ~]#

Best regards,
Peter

from moosefs.

FreeBSD hostname 10.0-RELEASE-p3 FreeBSD 10.0-RELEASE-p3 #0: Tue May 13 18:31:10 UTC 2014     [email protected]:/usr/obj/usr/src/sys/GENERIC  amd64

[root@s4 ~]# mfsmount -V
MFS version 2.0.89-1
FUSE library version: 2.9.5
mount_fusefs [fuse4bsd] version: 0.3.9-pre1

We have 510931 file in this folder, mainly small ones up to 1MB. We had this problem also before upgrade from 2.x.x.

from moosefs.

After remounting everything looks OK now (we will still observe it for some time). Strange thing, I hope it will no show up later on production env.

from moosefs.

This is FreeBSD related. FreeBSD just before close performs 'truncate' command with current file size. Such 'truncate' doesn't change file size because file size is the same, but it changes ctime+mtime (which is correct according to posix). FreeBSD does it only first time you read file - this is why you probably notice it only from time to time.

We've fixed that in 3.0.75 (commit: b48ff07)

from moosefs.