Re: [patch] Converting writeback linked lists to a tree based data structure

[Fengguang Wu <wfg@mail.ustc.edu.cn>]

On Wed, Jan 16, 2008 at 10:55:28AM -0800, Michael Rubin wrote:
> On Jan 15, 2008 7:01 PM, Fengguang Wu <wfg@mail.ustc.edu.cn> wrote:
> > Basically I think rbtree is an overkill to do time based ordering.
> > Sorry, Michael. But s_dirty would be enough for that. Plus, s_more_io
> > provides fair queuing between small/large files, and s_more_io_wait
> > provides waiting mechanism for blocked inodes.
> 
> I think the flush_tree (which is a little more than just an rbtree)
> provides the same queuing mechanisms that the three or four lists
> heads do and manages to do it in one structure. The i_flushed_when
> provides the ability to have blocked inodes wait their turn so to
> speak.
> 
> Another motivation behind the rbtree patch is to unify the data
> structure that handles the priority and mechanism of how we write out
> the pages of the inodes. There are some ideas about introducing
> priority schemes for QOS and such in the future. I am not saying this
> patch is about making that happen, but the idea is to if possible
> unify the four stages of lists into a single structure to facilitate
> efforts like that.

Yeah, rbtree is better than list_heads after all. Let's make it happen.