From owner-freebsd-current@freebsd.org  Fri Mar  9 12:18:13 2018
Return-Path: <owner-freebsd-current@freebsd.org>
Delivered-To: freebsd-current@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id B81C9F490CA
 for <freebsd-current@mailman.ysv.freebsd.org>;
 Fri,  9 Mar 2018 12:18:13 +0000 (UTC) (envelope-from slw@zxy.spb.ru)
Received: from zxy.spb.ru (zxy.spb.ru [195.70.199.98])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id 510DE742C6
 for <freebsd-current@freebsd.org>; Fri,  9 Mar 2018 12:18:13 +0000 (UTC)
 (envelope-from slw@zxy.spb.ru)
Received: from slw by zxy.spb.ru with local (Exim 4.86 (FreeBSD))
 (envelope-from <slw@zxy.spb.ru>)
 id 1euGiJ-0000FK-NM; Fri, 09 Mar 2018 15:01:31 +0300
Date: Fri, 9 Mar 2018 15:01:31 +0300
From: Slawa Olhovchenkov <slw@zxy.spb.ru>
To: Arshan Khanifar <arshan@freebsdfoundation.org>
Cc: freebsd-current@freebsd.org
Subject: Re: Performance Benchmark for PTI (aka Meltdown mitigation)
Message-ID: <20180309120131.GA38546@zxy.spb.ru>
References: <CADMyxqs93mbwxJB4C03LMfz5g3T45=n9NWBet_Wa22v4BO4LLA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CADMyxqs93mbwxJB4C03LMfz5g3T45=n9NWBet_Wa22v4BO4LLA@mail.gmail.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
X-SA-Exim-Connect-IP: <locally generated>
X-SA-Exim-Mail-From: slw@zxy.spb.ru
X-SA-Exim-Scanned: No (on zxy.spb.ru); SAEximRunCond expanded to false
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.25
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
 <freebsd-current.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-current>, 
 <mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current/>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-current>, 
 <mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 09 Mar 2018 12:18:13 -0000

On Thu, Mar 08, 2018 at 05:04:11PM -0500, Arshan Khanifar wrote:

> Executive Summary:
> - The PTI feature increases the system call times by more than 100%.
> - As a macrobenchmark, buildworld was used. Wall clock and user time
> showed no statistically-significant changes, while system time
> increased by less than 5%.
> 
> This email contains the results for benchmarking the performance of the
> PTI patch on FreeBSD 12-current. As a microbenchmark, timing of
> getppid(2) system call was used, and as a macrobenchmark, a number of
> buildworld tasks were timed.
> 

Can you also run pre-patched kernel?