Re: [PATCH] various allocator optimizations

[Chris Mason <mason@suse.com>]

On Wed, 2003-03-12 at 02:12, Oleg Drokin wrote:

> > > No, it uses the left neighbor in the tree.  Please correct me if I am 
> > > wrong, because if I am wrong we have a bug.
> > It uses the left neighbor in the tree once the file has a starting
> > block.  But the first starting block comes by searching from block #0.
> 
> No, this is not correct.
> We look at the left neighbor.
> See the get_left_neighbor() in bitmap.c,
> first we make the search_start to be a block number of last path
> element (if there is path at all of course which may be not there in some
> cases), ans then check if we are allocating indirect block and if there is
> non zero element in current indirect item in path, if there is non-zero element,
> we take it as new search_start, otherwise it still contains blocknumber of
> left neighbor.

Right, I missed the hint->search_start = bh->b_blocknr for when we don't
find an indirect item.

This is better, so the search will start from the bh with the stat data
for a new file, but it depends on the last path element being in a good
position relative to the rest of the files in the directory.

-chris