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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH] Huge TLB performance improvement
Date: Sun, 12 Nov 2006 20:42:58 +0000
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To: qemu-devel@nongnu.org

> A patch which flushes up to 1/32nd of the jump buffer indiscriminately
> cuts it to 1:11-1:13.
>
> Here's that last patch.  It changes the hash function so that entries
> from a particular page are always grouped together in tb_jmp_cache,
> then finds the possibly two affected ranges and memsets them clear.
> Thoughts?  Is this acceptable, where else should it be tested besides
> MIPS?  I haven't fine-tuned the numbers; it currently allows for max 64
> cached jump targets per target page, but that could be made higher or
> lower.

I've applied this patch.  It seems a reasonable compromise solution.

I tested a couple of different x86 guests, and couldn't measure any 
significant difference in performance.

Paul