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Cc: Anton Blanchard <anton@samba.org>, Linus Torvalds <torvalds@transmeta.com>,
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Subject: Re: [PATCH] Radix-tree pagecache for 2.5
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From: Momchil Velikov <velco@fadata.bg>
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Date: 01 Feb 2002 11:01:50 +0200
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>>>>> "Ingo" == Ingo Molnar <mingo@elte.hu> writes:

Ingo> On 1 Feb 2002, Momchil Velikov wrote:
>> So, we can use a read-write spinlock instead ->i_shared_lock, ok ?

Ingo> using read-write locks does not solve the scalability problem: the problem
Ingo> is the bouncing of the spinlock cacheline from CPU to CPU.

Does cache line bounce (shared somewhere -> exclusive elsewhere) cost
more that a simple miss (present nowhere -> exclusive somewhere) ?

Regards,
-velco

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