From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f44.google.com ([74.125.82.44]:37124 "EHLO mail-wm0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751273AbcBLRis (ORCPT ); Fri, 12 Feb 2016 12:38:48 -0500 Received: by mail-wm0-f44.google.com with SMTP id g62so29050423wme.0 for ; Fri, 12 Feb 2016 09:38:48 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20160212165319.GB7928@thunk.org> References: <87twlee9to.fsf@tassilo.jf.intel.com> <20160212133825.GJ11298@thunk.org> <20160212165319.GB7928@thunk.org> Date: Fri, 12 Feb 2016 18:38:47 +0100 Message-ID: Subject: Re: EXT4 vs LVM performance for VMs From: Premysl Kouril To: "Theodore Ts'o" Cc: Andi Kleen , linux-fsdevel@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-fsdevel-owner@vger.kernel.org List-ID: > All of this being said, what are you trying to do? If you are happy > using LVM, feel free to use it. If there are specific features that > you want out of the file system, it's best that you explicitly > identify what you want, and so we can minimize the cost of the > features of what you want. We are trying to decide whether to use filesystem or LVM for VM storage. It's not that we are happy with LVM - while it performs better there are limitations on LVM side especially when it comes to manageability (for example certain features in OpenStack do only fork if VM is file-based). So, in short, if we would make filesystem to perform better we would rather use filesystem than LVM, (and we don't really have any special requirements in terms of filesystem features). And in order for us to make a good decision I wanted to ask community, if our observations and resultant numbers make sense. Cheers, Prema