Hi Peter,
Sorry to bother you again, I was looking at the filesystem code for ufs.h
and I found that there are some metadata which is highly dependent on
whether the OS support 32bit or 64bit.
Snippet of ufs super block.
__fs64 fs_size; /* number of blocks in fs */
__fs64 fs_dsize; /* number of data blocks in
fs */
__fs64 fs_csaddr; /* blk addr of cyl grp
summary area */
__fs64 fs_pendingblocks;/* blocks in process of
being freed */
Number of data blocks supported on 64-bit(UFS) filesytem will be more then
that of the 32-bit (UFS) filesystem. So if we want 32-bit UFS filesystem(on
32 bit OS) to support data block as many as 64-bit UFS file sytem then we
have to modify UFS 32 bit filesystem.
So my question is, whether the 64-bit filesystem is supported on 32-bit OS?
I think it can be supported but with some changes in metadata structure
which will definitely add some performance hit...
Please confirm if this understanding is correct or not!!
-Manish R
On Sun, Aug 16, 2009 at 8:17 PM, manish <rangankarman...@gmail.com> wrote:
> Thanks Peter... I had this question because one of the project I am working
> on had a two different flavour of UFS.. one is UFS and other one is UFS64
> bit, ported on proprietary OS.
> -Manish
>
>
> On Sun, Aug 16, 2009 at 5:26 PM, Peter Teoh <htmldevelo...@gmail.com>wrote:
>
>> thanks for the confirmation.....the only thing that matters is
>> performance. as the data structure for the VFS layer is independent
>> (generally, i think) of 64 or 32bit kernel, so it should be indep of
>> 64/32bit kernel, but because 64bit have a larger data I/O rate, so
>> performance should be higher....at the expense of more memory
>> consumed......
>>
>> On Sun, Aug 16, 2009 at 6:09 PM, SandeepKsinha<sandeepksi...@gmail.com>
>> wrote:
>> > Hi Manish,
>> >
>> > On Sat, Aug 15, 2009 at 9:20 PM, Peter Teoh <htmldevelo...@gmail.com>
>> wrote:
>> >>
>> >> i don't think there is such a thing as 32/64 bit filesystem.
>> >> Filesystem type does not need to be linked to the OS's 32/64 bit
>> >> architecture. Ie, ext2 or ext3, is the same when mounted in either
>> >> filesystem. but the content within filesystem does matter, eg, if it
>> >> is 32/64bit executable etc.
>> >
>> > This is true !!!!
>> >
>> >
>> > Regards,
>> > Sandeep.
>> >
>> >
>> >
>> >
>> >
>> >
>> > “To learn is to change. Education is a process that changes the
>> learner.”
>> >
>> >
>> >
>> >
>> >>
>> >> On Sat, Aug 15, 2009 at 1:37 AM, manish<rangankarman...@gmail.com>
>> wrote:
>> >> > Hi All,
>> >> >
>> >> > I have basic query!!
>> >> >
>> >> > I can have 32 and 64 bit filesystem on 64-bit kernel. Is it possible
>> to
>> >> > have 64-bit filesystem on 32 bit kernel? Does linux support it?
>> >> >
>> >> > -Manish R
>> >>
>> >>
>> >>
>> >> --
>> >> Regards,
>> >> Peter Teoh
>> >>
>> >> --
>> >> To unsubscribe from this list: send an email with
>> >> "unsubscribe kernelnewbies" to ecar...@nl.linux.org
>> >> Please read the FAQ at http://kernelnewbies.org/FAQ
>> >>
>> >
>> >
>>
>>
>>
>> --
>> Regards,
>> Peter Teoh
>>
>
>
