Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753689AbdHIQBQ (ORCPT ); Wed, 9 Aug 2017 12:01:16 -0400 Received: from verein.lst.de ([213.95.11.211]:54239 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752661AbdHIQBN (ORCPT ); Wed, 9 Aug 2017 12:01:13 -0400 Date: Wed, 9 Aug 2017 18:01:11 +0200 From: Christoph Hellwig To: Paolo Bonzini Cc: "Richard W.M. Jones" , Christoph Hellwig , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, "Martin K. Petersen" Subject: Re: Increased memory usage with scsi-mq Message-ID: <20170809160111.GC3141@lst.de> References: <20170804210035.GA10017@redhat.com> <20170805084436.GA14264@lst.de> <20170805092704.GD20914@redhat.com> <20170805133954.GA17694@lst.de> <20170805155103.GE20914@redhat.com> <20170807122701.GH20914@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 467 Lines: 8 On Mon, Aug 07, 2017 at 03:07:48PM +0200, Paolo Bonzini wrote: > can_queue should depend on the virtqueue size, which unfortunately can > vary for each virtio-scsi device in theory. The virtqueue size is > retrieved by drivers/virtio prior to calling vring_create_virtqueue, and > in QEMU it is the second argument to virtio_add_queue. Why is that unfortunate? We don't even have to set can_queue in the host template, we can dynamically set it on per-host basis.