From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pieter De Wit Subject: Re: Is partition alignment needed for RAID partitions ? Date: Tue, 31 Dec 2013 14:05:15 +1300 Message-ID: <52C2184B.5030403@insync.za.net> References: <52C08E63.8020800@insync.za.net> <52C11929.3070600@hardwarefreak.com> <52C12F8B.6080507@insync.za.net> <52C14FB8.8080005@hardwarefreak.com> <52C162A7.1080309@insync.za.net> <52C1A8F0.2030208@hardwarefreak.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <52C1A8F0.2030208@hardwarefreak.com> Sender: linux-raid-owner@vger.kernel.org To: stan@hardwarefreak.com, linux-raid List-Id: linux-raid.ids Hi Stan, > You're welcome. Eventually you get to the bottom of this. > I think this moment has arrived :) I did some fio tests from all levels, raw disk, raw md device, raw LV, filesystem (ext4) on top of LV. All read and write tests came back with +- 120MB/s (mostly 128, but let's tone it down just for stats) I did a read,write and mixed test against the NAS: The read and write tests came back at 60MB/s, the mixed came in at 11MB/s. I ran a network test from my desktop to the server, using iperf and it got up to 80MB/s, add to that the sync traffic of 10-15MB and you have a pretty full gig pipe. The desktop nic is a crappy onboard one, so I am quite happy with those stats. Just "FYI" - they are all linked with a Cisco 3750G, the NAS has 2xgig ports in an etherchannel This leaves me only two conclusions: 1) pvmove isn't as fast as I think - it might be due to some checksums or some other process (I know it creates a small mirror of a PE and then breaks it - rinse repeat for all PEs) 2) That is just the limit for this system, "it is what it is" Either way - I think I have taken up enough of the list time, so thank you very much for the in-depth answers ! I still have access to the NAS until at least 13/01/2014 if you want to do more checks/tests. Have a good 2014! Cheers, Pieter