From mboxrd@z Thu Jan 1 00:00:00 1970 References: <66e4dbc1-ca00-3abf-5100-d19f7439a281@magenta.tv> <6e53a6f7-9896-2905-92ad-6b9c36f565ab@redhat.com> <39a2408c600ed4caf00724eb72c191c2@assyoma.it> From: Zdenek Kabelac Message-ID: <326c998e-67f8-6331-c8f1-a22e8c06fd98@redhat.com> Date: Fri, 22 Jun 2018 22:07:11 +0200 MIME-Version: 1.0 In-Reply-To: <39a2408c600ed4caf00724eb72c191c2@assyoma.it> Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [linux-lvm] Unable to un-cache logical volume when chunk size is over 1MiB 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 , Gionatan Danti Cc: Ryan Launchbury Dne 22.6.2018 v 20:13 Gionatan Danti napsal(a): > Il 20-06-2018 12:15 Zdenek Kabelac ha scritto: >> Hi >> >> Aren't there any kernel write errors in your 'dmegs'. >> LV becomes fragile if the associated devices with cache are having HW >> issues (disk read/write errors) >> >> Zdenek > > Is that true even when using a writethrough cache mode? With writethrough - all writes are first committed on 'origin' disk - before they are ack back to writing apps - so cache can be through away anytime. When cache will experience write error - it will become invalidate and will need to be dropped - but this thing is not automated ATM - so admin works is needed to handle this task. Regards Zdenek