From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1A098C433FE for ; Sun, 30 Jan 2022 01:21:41 +0000 (UTC) Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-369-tTJzdqf1MfOW9Ar5wQ2t7Q-1; Sat, 29 Jan 2022 20:21:36 -0500 X-MC-Unique: tTJzdqf1MfOW9Ar5wQ2t7Q-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7477B1083F60; Sun, 30 Jan 2022 01:21:30 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E493D1002390; Sun, 30 Jan 2022 01:21:27 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 9C32A1809CB8; Sun, 30 Jan 2022 01:21:19 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 20U1LG16024380 for ; Sat, 29 Jan 2022 20:21:16 -0500 Received: by smtp.corp.redhat.com (Postfix) id 47EDAC159B3; Sun, 30 Jan 2022 01:21:16 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast05.extmail.prod.ext.rdu2.redhat.com [10.11.55.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 43BD4C1D3AD for ; Sun, 30 Jan 2022 01:21:16 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-2.mimecast.com [205.139.110.61]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2B192802E5E for ; Sun, 30 Jan 2022 01:21:16 +0000 (UTC) Received: from out1-smtp.messagingengine.com (out1-smtp.messagingengine.com [66.111.4.25]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-224-rGMr1JvpMLeZ_pAEO_9x4g-1; Sat, 29 Jan 2022 20:21:13 -0500 X-MC-Unique: rGMr1JvpMLeZ_pAEO_9x4g-1 Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.nyi.internal (Postfix) with ESMTP id C60585C009F; Sat, 29 Jan 2022 20:21:12 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute5.internal (MEProxy); Sat, 29 Jan 2022 20:21:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:sender:subject:subject:to:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm1; bh=bG5nEu1edydidT4fY asAz1pfx8nNquxYLlmN8ZH0leI=; b=mNwabqA/hsvrrxk4vwexkoCk9i+b6IWL2 /1dYxGzo9kYEfqXiULQhhK6+jDN/6xXCkiI1BLN5lRfyF/amcWl9tgp/l9MJxMdU JIXPe9DWSFzn9qRjMApe2Gjzx47pePwlZBcR8vffnTzh9JErYXqPuLcKXBVHSUug D4xui8hGPw37SxRGwg6ZAbbwuglpI4NBXtx1XGa2Za1sx96hrxSvoiJiaKDzAZZ7 p6uOwDtuS9v173/sdXB6TI4x7ICH9YBVh/0TG8QYzSV6ulDbjD+PoeEDdbR9UnXG ObZJkwfei/Vqw4lLkyqJ8+uoOp+mluRVSuwpn3LuxjUPffB+TJAOQ== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvvddrfeekgddufecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpeffhffvuffkfhggtggujgesghdtreertddtjeenucfhrhhomhepffgvmhhiucfo rghrihgvucfqsggvnhhouhhruceouggvmhhisehinhhvihhsihgslhgvthhhihhnghhslh grsgdrtghomheqnecuggftrfgrthhtvghrnhepheehtdekhffggeeltdejfeejudetudei ieeliedukedvkedvueeuheffveetuddtnecuffhomhgrihhnpehrvgguhhgrthdrtghomh enucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpeguvghm ihesihhnvhhishhisghlvghthhhinhhgshhlrggsrdgtohhm X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Sat, 29 Jan 2022 20:21:12 -0500 (EST) Date: Sat, 29 Jan 2022 20:20:49 -0500 From: Demi Marie Obenour To: Zdenek Kabelac Message-ID: References: <9156ffae-650d-198d-5c7a-32f84dbcb332@gmail.com> <83468eda-6697-5f15-d949-e23611cded84@gmail.com> MIME-Version: 1.0 In-Reply-To: <83468eda-6697-5f15-d949-e23611cded84@gmail.com> X-Scanned-By: MIMEDefang 2.85 on 10.11.54.8 X-loop: linux-lvm@redhat.com Cc: LVM general discussion and development Subject: Re: [linux-lvm] Running thin_trim before activating a thin pool X-BeenThere: linux-lvm@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============5859683206754854477==" Sender: linux-lvm-bounces@redhat.com Errors-To: linux-lvm-bounces@redhat.com X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 --===============5859683206754854477== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="RfixY7QTc3n24Uw2" Content-Disposition: inline --RfixY7QTc3n24Uw2 Content-Type: text/plain; protected-headers=v1; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Date: Sat, 29 Jan 2022 20:20:49 -0500 From: Demi Marie Obenour To: Zdenek Kabelac Cc: LVM general discussion and development Subject: Re: Running thin_trim before activating a thin pool On Sat, Jan 29, 2022 at 10:40:34PM +0100, Zdenek Kabelac wrote: > Dne 29. 01. 22 v 21:09 Demi Marie Obenour napsal(a): > > On Sat, Jan 29, 2022 at 08:42:21PM +0100, Zdenek Kabelac wrote: > > > Dne 29. 01. 22 v 19:52 Demi Marie Obenour napsal(a): > > > > Is it possible to configure LVM2 so that it runs thin_trim before it > > > > activates a thin pool? Qubes OS currently runs blkdiscard on every= thin > > > > volume before deleting it, which is slow and unreliable. Would run= ning > > > > thin_trim during system startup provide a better alternative? > > >=20 > > > Hi > > >=20 > > >=20 > > > Nope there is currently no support from lvm2 side for this. > > > Feel free to open RFE. > >=20 > > Done: https://bugzilla.redhat.com/show_bug.cgi?id=3D2048160 > >=20 > >=20 >=20 > Thanks >=20 > Although your use-case Thinpool on top of VDO is not really a good plan a= nd > there is a good reason behind why lvm2 does not support this device stack > directly (aka thin-pool data LV as VDO LV). > I'd say you are stepping on very very thin ice... Thin pool on VDO is not my actual use-case. The actual reason for the ticket is slow discards of thin devices that are about to be deleted; you can find more details in the linked GitHub issue. That said, now I am curious why you state that dm-thin on top of dm-vdo (that is, userspace/filesystem/VM/etc =E2=87=92 dm-thin data (*not* metadata) =E2=87= =92 dm-vdo =E2=87=92 hardware/dm-crypt/etc) is a bad idea. It seems to be a decent way to add support for efficient snapshots of data stored on a VDO volume, and to have multiple volumes on top of a single VDO volume. Furthermore, https://access.redhat.com/articles/2106521#vdo recommends exactly this use-case. Or am I misunderstanding you? > Also I assume you have already checked performance of discard on VDO, but= I > would not want to run this operation frequently on any larger volume... I have never actually used VDO myself, although the documentation does warn about this. --=20 Sincerely, Demi Marie Obenour (she/her/hers) Invisible Things Lab --RfixY7QTc3n24Uw2 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdodNnxM2uiJZBxxxsoi1X/+cIsEFAmH16AUACgkQsoi1X/+c IsGqKQ/+No7tcfxbrK6YQn9tTTVqQFioaeR+84e2UuV9iwgeLIu2GFdH10tQJu4z YjNrzan8HJtgiY50sPb1+b2FtuTo68UN3f9nr2Dvzhz9MbmCz3LoJlyEmqVxmqDw a4tYdEOTLdRWSTjMreMWF9877rTnA+39BsaBHOO4EI4K+s5FxczhdWklsLHqvJsB lGvd8IF3aKXGx4DcCHr6X2Dlqs9J3fyoURmfj2dlwVaz7Bqb0tkW871ZD1ub+nbr +4NkUnUYl65xFb6SlXfweTTFEZjvN6vN/D1yflgW3eNWCWd929/D8DPld1/beSdL YIrAEJKpKkWJIzsjcmTEYd1qfyuB3+C5YFG2vCISFkdEIiGmjYyqxBwNEFNUM4ks N+rvKp5QzN9+ee1KYYoxJZakKIImRlpl8zOor1q073vJOw/cBox6zy27RV51e9vU btnBMaiAwJTxtUddA+HkH57xGa/XXXGswsMc38CQHJ4QwpFsrV+wC5gG7cbeYawI q/9S83+mqmePlzlBnZSDFINtGdUF4hGBOxTD5fpKhPe0c6AcW3iZiIltzY5IPWxO gJJbtFSPxY2sTBZeiQSklCJAW+dIqoIWTHvE676AgCpPCLhyEGy8rQ3ntJMbFMHp 6I/ZCu8/W3PEGTtu1VXV+35GKy2VY9R51tNLRoubRmRln23CM/o= =Hvvz -----END PGP SIGNATURE----- --RfixY7QTc3n24Uw2-- --===============5859683206754854477== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://listman.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ --===============5859683206754854477==--