From: Avi Kivity <avi@redhat.com>
To: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Cc: mtosatti@redhat.com, kvm@vger.kernel.org
Subject: Re: [PATCH 1/3] KVM: MMU: Make pte_list_desc fit cache lines well
Date: Thu, 15 Mar 2012 11:22:21 +0200 [thread overview]
Message-ID: <4F61B4CD.5020205@redhat.com> (raw)
In-Reply-To: <20120315181943.66eb7284.yoshikawa.takuya@oss.ntt.co.jp>
On 03/15/2012 11:19 AM, Takuya Yoshikawa wrote:
> We have PTE_LIST_EXT + 1 pointers in this structure and these 40/20
> bytes do not fit cache lines well. Furthermore some allocators may
> use 64/32-byte objects for the pte_list_desc cache.
>
> This patch solves this problem by raising PTE_LIST_EXT to 7.
>
> Note: with EPT/NPT we almost always have a single spte in each reverse
> mapping and nothing will be changed by this.
It might be better to drop it to 3. Without EPT/NPT, anonymous guest
pages will have two mappings (a kernel mapping and a user mapping).
Only file pages will have many mappings.
--
error compiling committee.c: too many arguments to function
next prev parent reply other threads:[~2012-03-15 9:22 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-15 9:18 [PATCH 0/3] KVM: MMU: Improve rmap handling Takuya Yoshikawa
2012-03-15 9:19 ` [PATCH 1/3] KVM: MMU: Make pte_list_desc fit cache lines well Takuya Yoshikawa
2012-03-15 9:22 ` Avi Kivity [this message]
2012-03-15 9:20 ` [PATCH 2/3] KVM: MMU: Improve iteration over sptes linked by rmap Takuya Yoshikawa
2012-03-15 9:44 ` Avi Kivity
2012-03-15 10:25 ` Takuya Yoshikawa
2012-03-15 9:21 ` [PATCH 3/3] KVM: MMU: Separate trivial NULL check out from rmap_get_next() Takuya Yoshikawa
2012-03-15 9:49 ` Avi Kivity
2012-03-15 10:15 ` Takuya Yoshikawa
2012-03-15 12:01 ` Avi Kivity
2012-03-15 13:41 ` Takuya Yoshikawa
2012-03-15 13:45 ` Avi Kivity
2012-03-15 13:46 ` Avi Kivity
2012-03-20 6:37 ` Takuya Yoshikawa
2012-03-20 11:56 ` Avi Kivity
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