From owner-freebsd-virtualization@FreeBSD.ORG Sat May 9 22:33:42 2015 Return-Path: Delivered-To: freebsd-virtualization@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 75809F14 for ; Sat, 9 May 2015 22:33:42 +0000 (UTC) Received: from mail-qk0-x236.google.com (mail-qk0-x236.google.com [IPv6:2607:f8b0:400d:c09::236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 3F5581C1D for ; Sat, 9 May 2015 22:33:42 +0000 (UTC) Received: by qkx62 with SMTP id 62so68227088qkx.0 for ; Sat, 09 May 2015 15:33:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=8d0zZ0HOJFqjd/TZStHLbUtAAshWg1j9HTFdE2WEW5k=; b=IjCrwN/k1lL3nKuKDkvyiqhwk4sOlMAwybdm7wvp49pcw5uXDXxCydS9B6GVPX3/t3 p2nKf35KDt6OT8dQKItN1QTumdv4Ft3vblZm5aDyxj67GU3z8+nhiQL+LB+cZjcqG6ev AMBcvHJPSQGyzActav56D1D6mBxfU0JN55V+so62qCblOGSWqdWRIzw+SgPlDJlFDi2Q geaM0wrshX9+Zg4Usn5w5vsDJ451kwOpJjruXXu1OgUqqNBDo9ok5y521l7bvwcfTijQ qP7PJo6DS20NlyhZ8TP4ZKji3GCYXr/7+l88q+TFBncmZQspZZrNeGiLaefTeCtDEhqj hkGA== MIME-Version: 1.0 X-Received: by 10.55.21.139 with SMTP id 11mr8833620qkv.19.1431210821220; Sat, 09 May 2015 15:33:41 -0700 (PDT) Received: by 10.140.39.148 with HTTP; Sat, 9 May 2015 15:33:41 -0700 (PDT) In-Reply-To: <7dd04a4cec612d18110a00b9020fd948@openmailbox.org> References: <7dd04a4cec612d18110a00b9020fd948@openmailbox.org> Date: Sat, 9 May 2015 15:33:41 -0700 Message-ID: Subject: Re: Is the BHyVe guest as suitable for high-performance disk IO as the host? From: Neel Natu To: Tinker Cc: "freebsd-virtualization@freebsd.org" Content-Type: text/plain; charset=UTF-8 X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.20 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: Sat, 09 May 2015 22:33:42 -0000 Hi Tinker, On Sat, May 9, 2015 at 9:49 AM, Tinker wrote: > Hi! > > For an environment with very heavy parallell IO, should the performance be > just as good in a BHyVe guest as in the FreeBSD host environment? > > What I thought of is that I guess within the host environment, the storage > subsystem should have all kinds of optimizations like an internal work queue > that pushes lots of work alinearly/asynchronously to the disk controller and > this way allows it, in turn, to give all its performance. > > Does the virtualized disk interface carry over all that goodness to the > guest? > bhyve creates 8 worker threads for each virtual disk controller (both ahci and virtio-blk). All guest I/O is handled asynchronously by these worker threads which provide parallelism. > (https://wiki.freebsd.org/bhyve seems to say yes, presuming you configure > BHyVe to run the virtual disk in AHCI mode?) > The wiki is out of date. Since r280037 the virtio-blk emulation also gets the benefits of using the block_if worker threads. best Neel > Thanks! > Tinker > > _______________________________________________ > freebsd-virtualization@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization > To unsubscribe, send any mail to > "freebsd-virtualization-unsubscribe@freebsd.org"