Dear Andreas, sorry for answering you so late (Christmas holidays ;), it seems that the information reported by the two commands you indicated, is different regarding the Access time of the file.
Is this a normal behaviour ? It seems that the MDS does not update the access time (we opened the file on the client to view it's content) ---> Issued on a lustre client # stat /scratch/pieretti/new.out File: `/scratch/pieretti/new.out' Size: 25959 Blocks: 56 IO Block: 2097152 regular file Device: a2f3dcdch/2733890780d Inode: 64740446 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 244/pieretti) Gid: (20053/ bb) Access: 2010-01-07 11:28:56.000000000 +0100 Modify: 2009-04-04 23:44:36.000000000 +0200 Change: 2009-06-19 00:35:21.000000000 +0200 ---> Issued on the mds # debugfs -c -R 'stat <64740446>' /dev/mapper/scratch_mdt debugfs 1.41.6.sun1 (30-May-2009) /dev/mapper/scratch_mdt: catastrophic mode - not reading inode or group bitmaps Inode: 64740446 Type: regular Mode: 0644 Flags: 0x0 Generation: 1095573155 Version: 0x00000000:00000000 User: 244 Group: 20053 Size: 0 File ACL: 0 Directory ACL: 0 Links: 1 Blockcount: 0 Fragment: Address: 0 Number: 0 Size: 0 ctime: 0x4a3ac129:c210ae38 -- Fri Jun 19 00:35:21 2009 atime: 0x4a3ac129:00000000 -- Fri Jun 19 00:35:21 2009 mtime: 0x49d7d4c4:00000000 -- Sat Apr 4 23:44:36 2009 crtime: 0x4a3ac129:c1969bb4 -- Fri Jun 19 00:35:21 2009 Size of extra inode fields: 28 Extended attributes stored in inode body: lov = "d0 0b d1 0b 01 00 00 00 5e dc db 03 00 00 00 00 00 00 00 00 00 00 00 00 00 00 10 00 08 00 00 00 f5 cd 0c 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 05 00 00 00 f5 cd 0c 00 00 00 0 0 00 00 00 00 00 00 00 00 00 00 00 00 00 04 00 00 00 f5 cd 0c 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 07 00 00 00 f5 cd 0c 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 06 00 00 00 f5 cd 0c 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 f5 cd 0c 00 00 00 00 00 0 0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f5 cd 0c 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 03 00 00 00 f5 cd 0c 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 02 00 00 00 " (22 4) BLOCKS: Thanks for your kindness Andrea Andreas Dilger wrote: > On 2009-12-23, at 04:11, Andrea Pieretti wrote: >> Dear Andreas, sorry for the delay, >> I work with Miguel, so i'll write for him. >> >> We have one question, >> is it possible (safe) to use debugfs on a mounted Lustre filesystem? > > Yes, this is safe unless you open the filesystem with "-w" (write mode). > Without that you shouldn't be able to modify the filesystem, and it is > safe. > >> Andreas Dilger wrote: >>> On 2009-12-16, at 06:28, Miguel Molowny Lopez wrote: >>> >>>> we are running lustre 1.8.1.1 on our storage cluster based on IB. >>>> >>>> We are building a "bulldozer" for a scratch area and we have found an >>>> odd behaviour in the e2scan utility (maybe a bug or a ... "defined >>>> behaviour" we don't know about). >>>> >>>> We have reproduced this behavior several time and we are having these >>>> results: >>>> - we run e2scan on the MDT to have the files newer than 3 days ago: >>>> command line used was like: >>>> * e2scan -l -N '2009-12-13' /dev/mapper/mdt >>>> or: >>>> * e2scan -l -n /tmp/file.timestamp /dev/mapper/mdt >>>> where file.timestamp has been created with the date of >>>> 3 days ago using touch >>>> The result is sorted and saved in a file called: 3daysago.list >>>> - we then run another e2scan looking for files newer than 2 days ago >>>> using the same command line and the result is sorted and saved in >>>> a file called: 2daysago.list >>>> >>>> The problem is that there are files whose last modification time is >>>> before the date at which we run the two e2scan commands (they were not >>>> modified during the run of e2scan) _BUT_ they appear only in the list >>>> 3daysago.list. Here is an example: >>>> >>>> - first run of e2scan at: Dec 15 16:20 (produce list 3daysago.list) >>>> - second run of e2scan at: Dec 15: 16:50 (produce list 2daysago.list) >>>> - file: /scratch/foobar.txt has mtime=ctime = Dec 14 03:19 >>>> >>>> This file is still on filesystem after the run of the two e2scan cmd >>>> well, this file appears only in the 3daysago.list. And this happen for >>>> a _LONG_ list of files. >>>> >>> >>> >>> This is definitely odd. It is worthwhile to check what the timestamp >>> is on the MDS, via "debugfs -c -R 'stat foobar.txt'", in addition to >>> checking via "stat /scratch/foobar.txt" in the filesystem. >>> >>> Cheers, Andreas >>> -- >>> Andreas Dilger >>> Sr. Staff Engineer, Lustre Group >>> Sun Microsystems of Canada, Inc. >>> >>> _______________________________________________ >>> Lustre-discuss mailing list >>> [email protected] >>> http://lists.lustre.org/mailman/listinfo/lustre-discuss >>> >> >> -- >> +------------------------------------------------------- >> + Andrea Pieretti >> + C.A.S.P.U.R., >> + Via dei Tizii, 6b >> + 00185 Roma ITALY >> + tel: +39-06-44486712 >> + mob: +39-328-4280841 >> + fax: +39-06-4957083 >> + e-mail: [email protected] >> + http://www.caspur.it >> +------------------------------------------------------- >> + >> + "Nitwit! Blubber! Oddment! Tweak!" >> + >> + Albus Percival Wulfric Brian Dumbledore >> +------------------------------------------------------- >> >> _______________________________________________ >> Lustre-discuss mailing list >> [email protected] >> http://lists.lustre.org/mailman/listinfo/lustre-discuss > > > Cheers, Andreas > -- > Andreas Dilger > Sr. Staff Engineer, Lustre Group > Sun Microsystems of Canada, Inc. > -- +------------------------------------------------------- + Andrea Pieretti + C.A.S.P.U.R., + Via dei Tizii, 6b + 00185 Roma ITALY + tel: +39-06-44486712 + mob: +39-328-4280841 + fax: +39-06-4957083 + e-mail: [email protected] + http://www.caspur.it +------------------------------------------------------- + + "Nitwit! Blubber! Oddment! Tweak!" + + Albus Percival Wulfric Brian Dumbledore +------------------------------------------------------- _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
