From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45907) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g9W5Y-0000yJ-Nz for qemu-devel@nongnu.org; Mon, 08 Oct 2018 10:00:54 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g9VrZ-0005Bi-OU for qemu-devel@nongnu.org; Mon, 08 Oct 2018 09:46:27 -0400 Received: from out3-smtp.messagingengine.com ([66.111.4.27]:48589) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1g9VrW-0005AY-43 for qemu-devel@nongnu.org; Mon, 08 Oct 2018 09:46:19 -0400 Date: Mon, 8 Oct 2018 09:46:16 -0400 From: "Emilio G. Cota" Message-ID: <20181008134616.GA25450@flamenco> References: <20181006214508.5331-1-cota@braap.org> <20181006214508.5331-7-cota@braap.org> <197b7649-0bc7-4a9a-021b-a308a1755cf1@amsat.org> <20181008014834.GA21299@flamenco> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181008014834.GA21299@flamenco> Subject: Re: [Qemu-devel] [RFC 6/6] cputlb: dynamically resize TLBs based on use rate List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= Cc: qemu-devel@nongnu.org, Alex =?iso-8859-1?Q?Benn=E9e?= , Pranith Kumar , Richard Henderson On Sun, Oct 07, 2018 at 21:48:34 -0400, Emilio G. Cota wrote: > - 70/40% use rate for growing/shrinking the TLB does not > seem a great choice, if one wants to avoid a pathological > case that can induce constant resizing. Imagine we got > exactly 70% use rate, and all TLB misses were compulsory > (i.e. a direct-mapped TLB would have not prevented a ^^^ > single miss). We'd then double the TLB size: I meant fully associative. E.