On Wed, Sep 29, 2010 at 09:52:14PM -0400, Christoph Hellwig wrote: > > Instead of doing the lock overkill on a still fundamentally global data How do you figure it is overkill? Actually the hash insertion/removal scales *really* well with per-bucket locks and it is a technique used and proven in other parts of the kernel like networking. Having a global lock there is certainly a huge bottleneck when you start increasing system size, so I don't know why you keep arguing against this. > structure what about replacing this with something better. I won't be doing this until after the scalability work. > you've already done this with the XFS icache, and while the per-AG > concept obviously can't be generic at least some of the lessons could be > applied. > > then again how much testing did this get anyway given that you > benchmark ran mostly XFS which doesn't hit this at all? > > If it was up to me I'd dtop this (and the bl_list addition) from the > series for now and wait for people who care about the scalability of > the generic icache code to come up with a better data structure. I do care about scalability of icache code. Given how simple this is, and seeing as we're about to have the big locking rework, I much prefer just fixing all the global locks now (which need to be fixed anyway). -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
