From mboxrd@z Thu Jan 1 00:00:00 1970 References: <42E7ED35-B32E-4C02-976A-7A9E5380EEA8@mac.com> From: Zdenek Kabelac Message-ID: <56cdaa13-a10a-a545-3cb6-cb454330df3f@redhat.com> Date: Thu, 14 Sep 2017 13:13:41 +0200 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [linux-lvm] Performance penalty for 4k requests on thin provisioned volume Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: LVM general discussion and development , Dale Stephenson Dne 14.9.2017 v 12:57 Gionatan Danti napsal(a): > On 14/09/2017 11:37, Zdenek Kabelac wrote: >> Sorry my typo here - is NOT ;) >> >> >> Zdenek > > Hi Zdenek, > as the only variable is the LVM volume type (fat/thick vs thin), why the thin > volume is slower than the thick one? > > I mean: all other things being equal, what is holding back the thin volume? So few more question: What is '/dev/sdb4' ? - is it also some fast SSD ? ([thinpool_tmeta] volgr0 ewi-ao---- 16.00g 1 0 /dev/sdb4:0-4095 - just checking to be sure your metadata device is not placed on rotational storage device)... What is your thin-pool chunk size - is it 64K ? - if your raise thin-pool chunk size up - is it getting any better ? Regards Zdenek