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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7784CC43334 for ; Wed, 29 Jun 2022 20:51:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229745AbiF2Uvx (ORCPT ); Wed, 29 Jun 2022 16:51:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41722 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229698AbiF2Uvw (ORCPT ); Wed, 29 Jun 2022 16:51:52 -0400 Received: from mail-pj1-x1033.google.com (mail-pj1-x1033.google.com [IPv6:2607:f8b0:4864:20::1033]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9120B3B57D for ; Wed, 29 Jun 2022 13:51:50 -0700 (PDT) Received: by mail-pj1-x1033.google.com with SMTP id x1-20020a17090abc8100b001ec7f8a51f5so708483pjr.0 for ; Wed, 29 Jun 2022 13:51:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:from:mime-version:subject:date:message-id :references:cc:in-reply-to:to; bh=QzwBZ8MiKHCkHQs6ubFBUeLJm2aPz3uAJ0SJNl3Iybc=; b=P/tFMAavejNGyZvqSFU2mkJlZXaYYqOnwQE6I2NFPUtuwMAstEtCx65ohUNqDaIZmC MsAwqyZeKRs499JxkU2CIVrGDOLJdfHytpqNlZwZO48HpP/ARLFvaaL+eryw7wawM0iN SPzlVDyieLswxUldskHOhk7PVNZ0u0ceT1c5GuTSafrVPdwF0Ov/UoN0H1zKGPUvGufb REMdzsHYS2Oh/or4pVyCRa/EPokRPQmRzskkzw6UCXAK1euBekAvQw1VNcLY4Vr7Feo7 QObeSNT9u7mwtvvY1JIoh3J0NqN26L3uE6OMzymevAKChr3x5DcvYH8e19VoQ7obUreI KxFA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:content-transfer-encoding:from:mime-version :subject:date:message-id:references:cc:in-reply-to:to; bh=QzwBZ8MiKHCkHQs6ubFBUeLJm2aPz3uAJ0SJNl3Iybc=; b=oAqUMolzZ0LXgXQ18TQraNzLp6+QLtenB1s6bx19Xd4Hu06cBcN/UMRdl9oISdsruY FHxHkN2NNjPJUImyIrec81njIKWnLAtb0/3rdMy1bBn46fDyhzTsy+El7GIDcMVG5Yrm BZp276AF9Vm0IwS9V133e7XgO/SiaFM9IxOawyzx1kU5XwcfmVoJgsAQoPi763XHEeV3 GrTW7sAhKYvXlvoBUZ33cS6NINKTnfSjT2QdmDARVkbCXEmCeJscyXQPxYfeWCJrht/D tRVuPlLbgN4afBAOI2qfdBqVV8rA6XK2AbiLZaFsCwoM1kS7YigbGvjK2OaOamA8YDdA hzRw== X-Gm-Message-State: AJIora+a3U7uJ1/BMok8QNtvexPoTa8jNZwBwjBPx//N71aNh71BQb+G rvv/kCJtNPKeRQJBVl1BSSStXg== X-Google-Smtp-Source: AGRyM1v1OkLy4OUlV7ZRW9VidqYwr1vCmgGeLPlNdNyB/wtkvJBb7FkK3KxiVGvVDMaUmxrLSBvU+A== X-Received: by 2002:a17:90b:1753:b0:1ef:2e75:8811 with SMTP id jf19-20020a17090b175300b001ef2e758811mr2120687pjb.22.1656535910048; Wed, 29 Jun 2022 13:51:50 -0700 (PDT) Received: from smtpclient.apple ([2600:380:b421:9fb9:5830:e8f6:f44a:f844]) by smtp.gmail.com with ESMTPSA id s9-20020a62e709000000b00527ab697c6asm6035747pfh.18.2022.06.29.13.51.49 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 29 Jun 2022 13:51:49 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable From: Jens Axboe Mime-Version: 1.0 (1.0) Subject: Re: [PATCH 5.20 1/4] block: add bio_rewind() API Date: Wed, 29 Jun 2022 14:51:48 -0600 Message-Id: <788DCE4B-8992-436B-B0D4-D101E9176345@kernel.dk> References: <20220629192646.aoj5c7xdqkifwjdg@moria.home.lan> Cc: Ming Lei , Mike Snitzer , linux-block@vger.kernel.org, dm-devel@redhat.com, Eric Biggers , Dmitry Monakhov , "Martin K . Petersen" In-Reply-To: <20220629192646.aoj5c7xdqkifwjdg@moria.home.lan> To: Kent Overstreet X-Mailer: iPhone Mail (19F77) Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Jun 29, 2022, at 1:26 PM, Kent Overstreet wro= te: >=20 > =EF=BB=BFOn Wed, Jun 29, 2022 at 01:00:52PM -0600, Jens Axboe wrote: >>> On 6/29/22 12:40 PM, Kent Overstreet wrote: >>> On Wed, Jun 29, 2022 at 11:16:10AM -0600, Jens Axboe wrote: >>>> Not sure what Christoph change you are referring to, but all the ones >>>> that I did to improve the init side were all backed by numbers I ran at= >>>> that time (and most/all of the commit messages will have that data). So= >>>> yes, it is indeed still very noticeable. Maybe not at 100K IOPS, but at= >>>> 10M on a core it most certainly is. >>>=20 >>> I was referring to 609be1066731fea86436f5f91022f82e592ab456. You >>> signed off on it, you must remember it...? >>=20 >> I'm sure we all remember each and every commit that gets applied, >> particularly with such a precise description of the change. >>=20 >>>> I'm all for having solid and maintainable code, obviously, but frivolou= s >>>> bloating of structures and more expensive setup cannot be hand waved >>>> away with "it doesn't matter if we touch 3 or 6 cachelines" because we >>>> obviously have a disagreement on that. >>>=20 >>> I wouldn't propose inflating struct _bio_ like that. But Jens, to be >>> blunt - I know we have different priorities in the way we write code. >>> Your writeback throttling code was buggy for _ages_ and I had users >>> hitting deadlocks there that I pinged you about, and I could not make >>> heads or tails of how that code was supposed to work and not for lack >>> of time spent trying! >>=20 >> OK Kent, you just wasted your 2nd chance here. Plonk. There are many >> rebuttals that could be made here, but I won't waste my time on it, nor >> would it be appropriate. >>=20 >> Come back when you know how to act professionally. Or don't come back >> at all. >=20 > Jens, you're just acting like your code is immune to criticism, and I don'= t have > an eyeroll big enough for that. We all know how you care about chasing eve= ry > last of those 10 million iops - and not much else. Kent, the time for your unsolicited opinions and attacks have passed. Just g= o away, not interested in interacting with you. You have no idea what you=E2= =80=99re talking about.=20 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 [170.10.133.124]) (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 7E444C433EF for ; Wed, 29 Jun 2022 20:58:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1656536296; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=Tsq8ZH+9z848g8mTdOvcpkRT2yNeOTyN2b4OUKL8GXE=; b=gqPaRuYS787a/YK4B54LNPxbVgcOAYlekVS3qzJP0i9x2DkSHKVheVo9MGVjiq5h/brp4T +3xGUHl9vU9JOC5rVQ8aLyicpvz3wV35s3Lp1hkHkdAPnHWNepp9zejqdGvm9e4ey4QgXZ iNKXY0AyJmhyAj4AkOGlPW5RYkXZObM= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-98-pTTCrqZ3NaW6I5ke_8ROXg-1; 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Wed, 29 Jun 2022 13:51:49 -0700 (PDT) From: Jens Axboe Mime-Version: 1.0 (1.0) Date: Wed, 29 Jun 2022 14:51:48 -0600 Message-Id: <788DCE4B-8992-436B-B0D4-D101E9176345@kernel.dk> References: <20220629192646.aoj5c7xdqkifwjdg@moria.home.lan> In-Reply-To: <20220629192646.aoj5c7xdqkifwjdg@moria.home.lan> To: Kent Overstreet X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 Subject: Re: [dm-devel] [PATCH 5.20 1/4] block: add bio_rewind() API X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Martin K . 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