From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH] x86: shrink 'struct domain',
	was already PAGE_SIZE
Date: Mon, 1 Feb 2016 11:07:09 +0000
Message-ID: <56AF3C5D.1010508@citrix.com>
References: <1454312541-12422-1-git-send-email-czuzu@bitdefender.com>
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To: Corneliu ZUZU <czuzu@bitdefender.com>, xen-devel@lists.xen.org
Cc: Keir Fraser <keir@xen.org>, Jan Beulich <jbeulich@suse.com>
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On 01/02/16 07:42, Corneliu ZUZU wrote:
> The X86 domain structure already occupied PAGE_SIZE (4096).
>
> Looking @ the memory layout of the structure, we could see that
> overall most was occupied by (used the pahole tool on domain.o):
>  * sizeof(domain.arch) = sizeof(arch_domain) = 3328 bytes.
>  * sizeof(domain.arch.hvm_domain) = 2224 bytes.
>  * sizeof(domain.arch.hvm_domain.pl_time) = 1088 bytes.
> This patch attempts to free some space, by making the pl_time
> field in hvm_domain dynamically allocated.
> We xzalloc/xfree it @ hvm_domain_initialise/hvm_domain_destroy.
>
> After this change, the domain structure shrunk w/ 1152 bytes (>1K!).
>
> Signed-off-by: Corneliu ZUZU <czuzu@bitdefender.com>

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

Thankyou for doing this - it is exactly the kind of change I had in mind.

~Andrew