Re: [PATCH 2/9] sector_t format string

Roman Zippel
2006-08-10T17:25:18Z

Hi,

On Thu, 10 Aug 2006, Andrew Morton wrote:

> For ext3 on x86:
>
> CONFIG_LBD=y:
>
> box:/usr/src/25> size fs/jbd/jbd.o fs/ext3/ext3.o
> text data bss dec hex filename
> 51076 8 32 51116 c7ac fs/jbd/jbd.o
> 87466 1020 4 88490 159aa fs/ext3/ext3.o
>
> CONFIG_LBD=n:
>
> box:/usr/src/25> size fs/jbd/jbd.o fs/ext3/ext3.o
> text data bss dec hex filename
> 51133 8 32 51173 c7e5 fs/jbd/jbd.o
> 87679 1020 4 88703 15a7f fs/ext3/ext3.o
>
> That's a grand total of 270 bytes of text saved. aka 0.19%.
>
> We'll save four bytes in the inode (unlikely to save anything due to slab
> packing).

sector_t is used in multiple structures (bio/request/buffer_head), which
quickly adds up.
ext3 is also currently not a very heavy sector_t user, if you try this
with block/ you get a more than 3% difference.

bye, Roman