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>Does anyone know how to change the TLB size? |
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Once you wade through all of the smart-ass replies |
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let me mention the following. |
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While the "size" of the TLB measured in number of |
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TLB-entries is cast in silicon, nearly all modern |
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CPU architectures (including the amd64/x86_64) have |
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scheme for increasing the effective capacity of the |
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TLB measured as the total amount of virtual address |
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space that can be mapped. This is because modern |
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TLB designs allow TLB entries to map varying size |
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windows of virtual address space. |
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The problem here is one of OS software. The size |
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of the window mapped by a TLB entry is intimately |
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related to the software's page size. The Linux |
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kernel is just now beginning to add support for page |
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sizes larger than 4K. This is turn ripples back |
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into file system design, free space management, etc. |
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Think pages sizes of 64KB or 1MB. IBM has announced |
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PPC support for 1GB TLB mappings! Such architectural |
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features are designed to support VERY large systems |
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with lots of memory working with VERY large datasets. |
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Anyway, it is going to be a while before such support |
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is available from a conservative release like Gentoo. |
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/john |
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-- |
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