regarding the inode64 mount option
Hi XFS-List!
I understand that the inode64 mount option allows inodes to be created beyond 1TB. There are also certain performance problems that can be cured by using this option when handling LOTS of inodes. During my tests i noticed that enabling it is like a one-way street. Inodes created with inode64 enabled aren't accessible when the option is left out.
Now i got a few questions:
- Does the inode64 option work only on 64bit architectures or is it also possible to use it with i686
- Is there a way to convert the inodes back
- Why doesn't the filesystem remember that inode64 was used in the past and enable it automatically
- Do i have to pass inode64 via grub / lilo if i want to use it on my root filesystem
I haven't found any definitive clear documentation abount the pro's and con's, so maybe you can give me some hints :-)
tia,
Michael
_______________________________________________
xfs mailing list
[email protected]
http://oss.sgi.com/mailman/listinfo/xfs
Quoted 2 lines · Michael Weissenbacher
Hi XFS-List!
I understand that the inode64 mount option allows inodes to be created beyond 1TB. There are also certain performance problems that can be cured by using this option when handling LOTS of inodes. During my tests i noticed that enabling it is like a one-way street. Inodes created with inode64 enabled aren't accessible when the option is left out.
Actually they should still be accessible, we just won't create new inodes not addressable by 32bit inode numbers.
Quoted 2 lines
Now i got a few questions:
- Does the inode64 option work only on 64bit architectures or is it also possible to use it with i686
It is available for 32bit kernels starting with kernel 2.6.29.
Quoted 1 line
- Is there a way to convert the inodes back
There's an xfs_reno tool ported from IRIX to renumber the inodes. I'll see if I can finally get it packaged.
Quoted 1 line
- Why doesn't the filesystem remember that inode64 was used in the past and enable it automatically
Good question. We could introduce a flag in the superblock for this.
Quoted 1 line
- Do i have to pass inode64 via grub / lilo if i want to use it on my root filesystem
Yes.
Quoted 1 line
I haven't found any definitive clear documentation abount the pro's and con's, so maybe you can give me some hints :-)
The only reason speaking against inode64 are old buggy programs that can't cope with a 64bit ino_t, Eric had a quite scary list of those in Fedora somewhere..
_______________________________________________
xfs mailing list
[email protected]
http://oss.sgi.com/mailman/listinfo/xfs
Quoted 1 line · Christoph Hellwig
On Thu, May 28, 2009 at 02:21:44PM +0200, Michael Weissenbacher
...
Quoted 6 lines
Quoted 2 lines
I haven't found any definitive clear documentation abount the pro's and con's, so maybe you can give me some hints :-)
The only reason speaking against inode64 are old buggy programs that can't cope with a 64bit
ino_t, Eric had a quite scary list of those in Fedora somewhere..
http://sandeen.net/wordpress/?p=9
-Eric
_______________________________________________
xfs mailing list
[email protected]
http://oss.sgi.com/mailman/listinfo/xfs
Hi Eric + Christoph!
Quoted 1 line
This is a scary list indeed! Does this apply only to Fedora on i686 or also to x86_64?
In general, does the inode64 option make sense at all on a partition that is <1TB in size?
Quoted 2 lines
Actually they should still be accessible, we just won't create new inodes not addressable by 32bit inode numbers.
Well, in my tests it didn't work. I tried this is on fedora core 6 with vanilla kernel 2.6.28.10 x86_64. See here:
(when mounted without inode64)
[root@mojave ~]# ls /backup/ -lha
ls: cannot access /backup/mojave_gentoo_backup: Invalid argument
total 8.0K
drwxr-xr-x 6 root root 99 2009-05-25 18:07 .
drwxr-xr-x 26 root root 4.0K 2009-05-28 17:38 ..
drwxr-xr-x 4 amandabackup disk 51 2009-05-07 15:46 amanda_holdings ?????????? ? ? ? ? ? mojave_gentoo_backup drwx--x--x 4 root root 41 2009-04-29 11:57 servers drwxrwxrwt 2 root root 6 2009-06-02 10:38 tmp
[root@mojave ~]# ls /backup/mojave_gentoo_backup -lha
ls: cannot access /backup/mojave_gentoo_backup: Invalid argument [root@mojave ~]#
(when mounted with inode64)
[root@mojave ~]# ls /backup/ -lha
total 12K
drwxr-xr-x 6 root root 99 2009-05-25 18:07 .
drwxr-xr-x 26 root root 4.0K 2009-05-28 17:38 ..
drwxr-xr-x 4 amandabackup disk 51 2009-05-07 15:46 amanda_holdings
drwxr-xr-x 23 root root 4.0K 2009-05-05 10:53 mojave_gentoo_backup drwx--x--x 4 root root 41 2009-04-29 11:57 servers drwxrwxrwt 2 root root 6 2009-06-02 10:38 tmp [root@mojave ~]# ls /backup/mojave_gentoo_backup/ -lha total 27M drwxr-xr-x 23 root root 4.0K 2009-05-05 10:53 . drwxr-xr-x 6 root root 99 2009-05-25 18:07 .. drwxr-xr-x 2 root root 10 2009-05-05 11:53 backup
(snipped)
The filesystem is consistent - xfs_check (3.0.1) doesn't report any problems.
thanks,
Michael
_______________________________________________
xfs mailing list
[email protected]
http://oss.sgi.com/mailman/listinfo/xfs
Quoted 5 lines · Michael Weissenbacher
Hi Eric + Christoph!
Quoted 1 line
This is a scary list indeed! Does this apply only to Fedora on i686 or also to
x86_64?In general, does the inode64 option make sense at all on a partition that is <1TB in size?
inode64 doesn't do anything on a partition smaller than 1TB.
Quoted 3 lines
Quoted 2 lines
Actually they should still be accessible, we just won't create new inodes not addressable by 32bit inode numbers.
Well, in my tests it didn't work.
Indeed. (I thought I already replied stating this, but found my mail in Drafts folder).
What you're seeing is expected result, which was observed in our environment as well.
[snip]
Quoted 1 line
The filesystem is consistent -
xfs_check(3.0.1) doesn't report any problems.
Right, filesystem is still consistent.
And xfs_check/xfs_repair has no idea that filesystem may be mounted without the inode64.
Felix
_______________________________________________
xfs mailing list
[email protected]
http://oss.sgi.com/mailman/listinfo/xfs
[my unsent mail from yesterday, mostly for the second blob]
Quoted 6 lines · Christoph Hellwig
Quoted 2 lines · Michael Weissenbacher
Hi XFS-List!
I understand that the inode64 mount option allows inodes to be created beyond 1TB. There are also certain performance problems that can be cured by using this option when handling LOTS of inodes. During my tests i noticed that enabling it is like a one-way street. Inodes created with inode64 enabled aren't accessible when the option is left out.Actually they should still be accessible, we just won't create new inodes not addressable by 32bit inode numbers.
The inodes are indeed accessible by most apps, but those 32bit apps using stat() (vs. stat64() ) will get confused and may bailout processing such inodes all together.
Quoted 8 lines
Quoted 3 lines
Now i got a few questions:
- Does the inode64 option work only on 64bit architectures or is it also possible to use it with i686It is available for 32bit kernels starting with kernel 2.6.29.
Quoted 1 line
- Is there a way to convert the inodes back
Quoted 7 lines
There's an
xfs_renotool ported from IRIX to renumber the inodes. I'll see if I can finally get it packaged.Quoted 2 lines
- Why doesn't the filesystem remember that inode64 was used in the past and enable it automatically
Good question. We could introduce a flag in the superblock for this.
Agree, it's a good idea to record that inode64 was used on previous mount, but I don't think we should enable it automatically. Though, providing the warning will be good.
Felix
_______________________________________________
xfs mailing list
[email protected]
http://oss.sgi.com/mailman/listinfo/xfs