From owner-freebsd-virtualization@freebsd.org Thu Feb 15 06:21:25 2018 Return-Path: Delivered-To: freebsd-virtualization@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 3E5EDF00909 for ; Thu, 15 Feb 2018 06:21:25 +0000 (UTC) (envelope-from FreeBSD@shaneware.biz) Received: from ipmailnode02.adl6.internode.on.net (ipmailnode02.adl6.internode.on.net [150.101.137.148]) by mx1.freebsd.org (Postfix) with ESMTP id 739FB84A5A for ; Thu, 15 Feb 2018 06:21:23 +0000 (UTC) (envelope-from FreeBSD@shaneware.biz) Received: from unknown (HELO leader.local) ([118.211.9.187]) by ipmail02.adl6.internode.on.net with ESMTP; 15 Feb 2018 16:46:12 +1030 Subject: Re: bhyve and contention To: "Rodney W. Grimes" Cc: tech-lists , freebsd-virtualization@freebsd.org References: <201802141910.w1EJAMQi054510@pdx.rh.CN85.dnsmgr.net> From: Shane Ambler Message-ID: <6fc388d9-388f-1cd3-ee8b-16d8e9204447@ShaneWare.Biz> Date: Thu, 15 Feb 2018 16:46:11 +1030 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: <201802141910.w1EJAMQi054510@pdx.rh.CN85.dnsmgr.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-AU Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: "Discussion of various virtualization techniques FreeBSD supports." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 15 Feb 2018 06:21:25 -0000 On 15/02/2018 05:40, Rodney W. Grimes wrote: > [ Charset UTF-8 unsupported, converting... ] >> On 14/02/2018 10:18, Peter Grehan wrote: >> Be sure not to pass the -S option to bhyve as it wires the guest memory. >> This was seen recently as sysutils/chyves uses it by default. > > This should be evaluated, if you do not pass -S you run into the > possible performance impact of swapping guest memory, which does > infact allow you more over commit, but at a pretty large > performance penality. The original question specified having 5 guests with 8G each on a host with 32G, so overcommitting ram was expected, wiring each guest in this setup will cause panics not swapping. > You need swap space if you are going to not pass -S and over commit, > if you do not have enough swap space for the over commit your system > runs out of swap and usually ends up killing random processes, and > random usually means the most important things you are running! The host has 64G swap setup. -- FreeBSD - the place to B...Software Developing Shane Ambler