On Tue, Nov 02, 2004 at 03:51:03PM +0100, Stefan Bader wrote: > Personally I would rather see path information moving into the path > selector We need some concrete examples of what information is missing and how other sorts of path selectors would benefit from it. > There are even some fields and functions in dm-mpath.c > (current_count) that are rather specific to a selector. That's a generic optimisation - you normally don't want to be recalculating which path to use for every single I/O - choose a path, then send the next X I/O down it before reassessing which to use. > For path selectors: what about per selector arguments? Probably, but first we need some concrete examples of arguments that can't be per-path. > For example the round-robin could take the number of io operations > before switching to the next path: > round-robin 1 1000 2 1 7:1 1 7:2 It already does, as a more-flexible per-path argument. Alasdair -- agk@xxxxxxxxxx