Messages in this thread |  | | | Date | Thu, 21 Feb 2008 11:16:58 +0530 | | From | Balbir Singh <> | | Subject | Re: [PATCH] Document huge memory/cache overhead of memory controller in Kconfig | |
Nick Piggin wrote:
>> 1. We could create something similar to mem_map, we would need to handle 4
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>> different ways of creating mem_map.
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>> 2. On x86 with 64 GB ram, if we decided to use vmalloc space, we would need
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>> 64 MB of vmalloc'ed memory
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> That's going to be a big job. You could probably do it quite easily for
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> flatmem (just store an offset into the start of your page array), and
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> maybe even sparsemem (add some "extra" information to the extents).
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>> I have not explored your latest suggestion of pfn <-> memory controller
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>> mapping yet. I'll explore it and see how that goes.
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> If you did that using a radix-tree, then it could be a runtime option
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> without having to use vmalloc. And you wouldn't have to care about
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> memory models. I'd say it will be the fastest way to get a prototype
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> running.
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OK, I'll explore and prototype the radix tree based approach and see how that goes.
--
Warm Regards,
Balbir Singh
Linux Technology Center
IBM, ISTL
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