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From: David Vrabel <david.vrabel@citrix.com>
To: Ben Catterall <Ben.Catterall@citrix.com>, xen-devel@lists.xenproject.org
Cc: keir@xen.org, jbeulich@suse.com, george.dunlap@eu.citrix.com,
	andrew.cooper3@citrix.com, tim@xen.org,
	Aravind.Gopalakrishnan@amd.com, suravee.suthikulpanit@amd.com,
	boris.ostrovsky@oracle.com, ian.campbell@citrix.com
Subject: Re: [PATCH RFC v2 0/4] HVM x86 deprivileged mode operations
Date: Thu, 3 Sep 2015 17:15:50 +0100	[thread overview]
Message-ID: <55E87236.4020705@citrix.com> (raw)
In-Reply-To: <1441296086-18209-1-git-send-email-Ben.Catterall@citrix.com>

On 03/09/15 17:01, Ben Catterall wrote:
> 
> Intel Intel 2.2GHz Xeon E5-2407 0 processor:
> --------------------------------------------
> 1.55e-06 seconds was the average time for performing the write without the
>          deprivileged code running.
> 
> 5.75e-06 seconds was the average time for performing the write with the
>          deprivileged code running.
> 
> So approximately 351% overhead
> 
> AMD Opteron 2376:
> -----------------
> 1.74e-06 seconds was the average time for performing the write without the
>          deprivileged code running.
> 3.10e-06 seconds was the average time for performing the write with an entry and
>          exit from deprvileged mode.
> 
> So approximately 178% overhead.

How does this compare to the overhead of passing the I/O through to qemu?

David

  parent reply	other threads:[~2015-09-03 16:16 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-09-03 16:01 [PATCH RFC v2 0/4] HVM x86 deprivileged mode operations Ben Catterall
2015-09-03 16:01 ` [PATCH RFC v2 1/4] HVM x86 deprivileged mode: Create deprivileged page tables Ben Catterall
2015-09-03 16:01 ` [PATCH RFC v2 2/4] HVM x86 deprivileged mode: Code for switching into/out of deprivileged mode Ben Catterall
2015-09-03 16:01 ` [PATCH RFC v2 3/4] HVM x86 deprivileged mode: Trap handlers for " Ben Catterall
2015-09-03 16:01 ` [PATCH RFC v2 4/4] HVM x86 deprivileged mode: Watchdog for DoS prevention Ben Catterall
2015-09-03 16:15 ` David Vrabel [this message]
2015-09-07 10:50   ` [PATCH RFC v2 0/4] HVM x86 deprivileged mode operations Ben Catterall
2015-09-04  8:33 ` Jan Beulich
2015-09-04  9:16   ` Ian Campbell
2015-09-04  9:31     ` Jan Beulich
2015-09-04 10:46 ` Fabio Fantoni
2015-09-08 10:58   ` Ben Catterall

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