Messages in this thread | | | Date | Fri, 14 Jun 2002 16:29:43 -0700 | From | William Lee Irwin III <> | Subject | Re: bio_chain: proposed solution for bio_alloc failure and large IO simplification |
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On Fri, Jun 14, 2002 at 04:00:52PM -0700, Andrew Morton wrote: > Everything is pretty much in place to do this now. The main piece > which is missing is the gang page allocator (Hi, Bill). > It'll be damn fast, and nicely scalable. It's all about reducing the > L1 cache footprint. Making best use of data when it is in cache. > Making best use of locks once they have been acquired. If it is > done right, it'll be almost as fast as 64k PAGE_CACHE_SIZE, with > none of its disadvantages. > In this context, bio_chain() is regression, because we're back > into doing stuff once-per-page, and longer per-page call graphs. > I'd rather not have to do it if it can be avoided.
gang_cpu is not quite ready to post, but work is happening on it and it's happening today -- I have a suitable target in hand and am preparing it for testing. The bits written thus far consist of a transparent per-cpu pool layer refilled using the gang transfer mechanism, and I'm in the process of refining that to non-prototypical code and extending it with appropriate deadlock avoidance so explicit gang allocation requests can be satisfied.
Cheers, Bill - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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