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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1CD72C43441 for ; Mon, 26 Nov 2018 11:28:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D324020672 for ; Mon, 26 Nov 2018 11:28:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D324020672 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-btrfs-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726511AbeKZWW0 (ORCPT ); Mon, 26 Nov 2018 17:22:26 -0500 Received: from mx2.suse.de ([195.135.220.15]:36844 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726266AbeKZWWZ (ORCPT ); Mon, 26 Nov 2018 17:22:25 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 8246CAEDA; Mon, 26 Nov 2018 11:28:33 +0000 (UTC) Subject: Re: [PATCH 4/8] btrfs: add ALLOC_CHUNK_FORCE to the flushing code To: Josef Bacik , linux-btrfs@vger.kernel.org, kernel-team@fb.com References: <20181121190313.24575-1-josef@toxicpanda.com> <20181121190313.24575-5-josef@toxicpanda.com> From: Nikolay Borisov Openpgp: preference=signencrypt Autocrypt: addr=nborisov@suse.com; prefer-encrypt=mutual; keydata= xsFNBFiKBz4BEADNHZmqwhuN6EAzXj9SpPpH/nSSP8YgfwoOqwrP+JR4pIqRK0AWWeWCSwmZ T7g+RbfPFlmQp+EwFWOtABXlKC54zgSf+uulGwx5JAUFVUIRBmnHOYi/lUiE0yhpnb1KCA7f u/W+DkwGerXqhhe9TvQoGwgCKNfzFPZoM+gZrm+kWv03QLUCr210n4cwaCPJ0Nr9Z3c582xc bCUVbsjt7BN0CFa2BByulrx5xD9sDAYIqfLCcZetAqsTRGxM7LD0kh5WlKzOeAXj5r8DOrU2 GdZS33uKZI/kZJZVytSmZpswDsKhnGzRN1BANGP8sC+WD4eRXajOmNh2HL4P+meO1TlM3GLl EQd2shHFY0qjEo7wxKZI1RyZZ5AgJnSmehrPCyuIyVY210CbMaIKHUIsTqRgY5GaNME24w7h TyyVCy2qAM8fLJ4Vw5bycM/u5xfWm7gyTb9V1TkZ3o1MTrEsrcqFiRrBY94Rs0oQkZvunqia c+NprYSaOG1Cta14o94eMH271Kka/reEwSZkC7T+o9hZ4zi2CcLcY0DXj0qdId7vUKSJjEep c++s8ncFekh1MPhkOgNj8pk17OAESanmDwksmzh1j12lgA5lTFPrJeRNu6/isC2zyZhTwMWs k3LkcTa8ZXxh0RfWAqgx/ogKPk4ZxOXQEZetkEyTFghbRH2BIwARAQABzSJOaWtvbGF5IEJv cmlzb3YgPG5ib3Jpc292QHN1c2UuZGU+wsF4BBMBAgAiBQJYijkSAhsDBgsJCAcDAgYVCAIJ CgsEFgIDAQIeAQIXgAAKCRBxvoJG5T8oV/B6D/9a8EcRPdHg8uLEPywuJR8URwXzkofT5bZE IfGF0Z+Lt2ADe+nLOXrwKsamhweUFAvwEUxxnndovRLPOpWerTOAl47lxad08080jXnGfYFS Dc+ew7C3SFI4tFFHln8Y22Q9075saZ2yQS1ywJy+TFPADIprAZXnPbbbNbGtJLoq0LTiESnD w/SUC6sfikYwGRS94Dc9qO4nWyEvBK3Ql8NkoY0Sjky3B0vL572Gq0ytILDDGYuZVo4alUs8 LeXS5ukoZIw1QYXVstDJQnYjFxYgoQ5uGVi4t7FsFM/6ykYDzbIPNOx49Rbh9W4uKsLVhTzG BDTzdvX4ARl9La2kCQIjjWRg+XGuBM5rxT/NaTS78PXjhqWNYlGc5OhO0l8e5DIS2tXwYMDY LuHYNkkpMFksBslldvNttSNei7xr5VwjVqW4vASk2Aak5AleXZS+xIq2FADPS/XSgIaepyTV tkfnyreep1pk09cjfXY4A7qpEFwazCRZg9LLvYVc2M2eFQHDMtXsH59nOMstXx2OtNMcx5p8 0a5FHXE/HoXz3p9bD0uIUq6p04VYOHsMasHqHPbsMAq9V2OCytJQPWwe46bBjYZCOwG0+x58 fBFreP/NiJNeTQPOa6FoxLOLXMuVtpbcXIqKQDoEte9aMpoj9L24f60G4q+pL/54ql2VRscK d87BTQRYigc+ARAAyJSq9EFk28++SLfg791xOh28tLI6Yr8wwEOvM3wKeTfTZd+caVb9gBBy wxYhIopKlK1zq2YP7ZjTP1aPJGoWvcQZ8fVFdK/1nW+Z8/NTjaOx1mfrrtTGtFxVBdSCgqBB jHTnlDYV1R5plJqK+ggEP1a0mr/rpQ9dFGvgf/5jkVpRnH6BY0aYFPprRL8ZCcdv2DeeicOO YMobD5g7g/poQzHLLeT0+y1qiLIFefNABLN06Lf0GBZC5l8hCM3Rpb4ObyQ4B9PmL/KTn2FV Xq/c0scGMdXD2QeWLePC+yLMhf1fZby1vVJ59pXGq+o7XXfYA7xX0JsTUNxVPx/MgK8aLjYW hX+TRA4bCr4uYt/S3ThDRywSX6Hr1lyp4FJBwgyb8iv42it8KvoeOsHqVbuCIGRCXqGGiaeX Wa0M/oxN1vJjMSIEVzBAPi16tztL/wQtFHJtZAdCnuzFAz8ue6GzvsyBj97pzkBVacwp3/Mw qbiu7sDz7yB0d7J2tFBJYNpVt/Lce6nQhrvon0VqiWeMHxgtQ4k92Eja9u80JDaKnHDdjdwq FUikZirB28UiLPQV6PvCckgIiukmz/5ctAfKpyYRGfez+JbAGl6iCvHYt/wAZ7Oqe/3Cirs5 KhaXBcMmJR1qo8QH8eYZ+qhFE3bSPH446+5oEw8A9v5oonKV7zMAEQEAAcLBXwQYAQIACQUC WIoHPgIbDAAKCRBxvoJG5T8oV1pyD/4zdXdOL0lhkSIjJWGqz7Idvo0wjVHSSQCbOwZDWNTN JBTP0BUxHpPu/Z8gRNNP9/k6i63T4eL1xjy4umTwJaej1X15H8Hsh+zakADyWHadbjcUXCkg OJK4NsfqhMuaIYIHbToi9K5pAKnV953xTrK6oYVyd/Rmkmb+wgsbYQJ0Ur1Ficwhp6qU1CaJ mJwFjaWaVgUERoxcejL4ruds66LM9Z1Qqgoer62ZneID6ovmzpCWbi2sfbz98+kW46aA/w8r 7sulgs1KXWhBSv5aWqKU8C4twKjlV2XsztUUsyrjHFj91j31pnHRklBgXHTD/pSRsN0UvM26 lPs0g3ryVlG5wiZ9+JbI3sKMfbdfdOeLxtL25ujs443rw1s/PVghphoeadVAKMPINeRCgoJH zZV/2Z/myWPRWWl/79amy/9MfxffZqO9rfugRBORY0ywPHLDdo9Kmzoxoxp9w3uTrTLZaT9M KIuxEcV8wcVjr+Wr9zRl06waOCkgrQbTPp631hToxo+4rA1jiQF2M80HAet65ytBVR2pFGZF zGYYLqiG+mpUZ+FPjxk9kpkRYz61mTLSY7tuFljExfJWMGfgSg1OxfLV631jV1TcdUnx+h3l Sqs2vMhAVt14zT8mpIuu2VNxcontxgVr1kzYA/tQg32fVRbGr449j1gw57BV9i0vww== Message-ID: <30bf1159-9bbc-96fb-89a2-41cf6b22df7b@suse.com> Date: Mon, 26 Nov 2018 13:28:32 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20181121190313.24575-5-josef@toxicpanda.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 21.11.18 г. 21:03 ч., Josef Bacik wrote: > With my change to no longer take into account the global reserve for > metadata allocation chunks we have this side-effect for mixed block > group fs'es where we are no longer allocating enough chunks for the > data/metadata requirements. To deal with this add a ALLOC_CHUNK_FORCE > step to the flushing state machine. This will only get used if we've > already made a full loop through the flushing machinery and tried > committing the transaction. If we have then we can try and force a > chunk allocation since we likely need it to make progress. This > resolves the issues I was seeing with the mixed bg tests in xfstests > with my previous patch. > > Signed-off-by: Josef Bacik Reviewed-by: Nikolay Borisov Still, my observation is that the metadata reclaim code is increasing in complexity for rather niche use cases or the details become way too subtle. > --- > fs/btrfs/ctree.h | 3 ++- > fs/btrfs/extent-tree.c | 18 +++++++++++++++++- > include/trace/events/btrfs.h | 1 + > 3 files changed, 20 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > index 0c6d589c8ce4..8ccc5019172b 100644 > --- a/fs/btrfs/ctree.h > +++ b/fs/btrfs/ctree.h > @@ -2750,7 +2750,8 @@ enum btrfs_flush_state { > FLUSH_DELALLOC = 5, > FLUSH_DELALLOC_WAIT = 6, > ALLOC_CHUNK = 7, > - COMMIT_TRANS = 8, > + ALLOC_CHUNK_FORCE = 8, > + COMMIT_TRANS = 9, > }; > > int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes); > diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c > index a91b3183dcae..e6bb6ce23c84 100644 > --- a/fs/btrfs/extent-tree.c > +++ b/fs/btrfs/extent-tree.c > @@ -4927,6 +4927,7 @@ static void flush_space(struct btrfs_fs_info *fs_info, > btrfs_end_transaction(trans); > break; > case ALLOC_CHUNK: > + case ALLOC_CHUNK_FORCE: > trans = btrfs_join_transaction(root); > if (IS_ERR(trans)) { > ret = PTR_ERR(trans); > @@ -4934,7 +4935,9 @@ static void flush_space(struct btrfs_fs_info *fs_info, > } > ret = do_chunk_alloc(trans, > btrfs_metadata_alloc_profile(fs_info), > - CHUNK_ALLOC_NO_FORCE); > + (state == ALLOC_CHUNK) ? > + CHUNK_ALLOC_NO_FORCE : > + CHUNK_ALLOC_FORCE); > btrfs_end_transaction(trans); > if (ret > 0 || ret == -ENOSPC) > ret = 0; > @@ -5070,6 +5073,19 @@ static void btrfs_async_reclaim_metadata_space(struct work_struct *work) > commit_cycles--; > } > > + /* > + * We don't want to force a chunk allocation until we've tried > + * pretty hard to reclaim space. Think of the case where we > + * free'd up a bunch of space and so have a lot of pinned space > + * to reclaim. We would rather use that than possibly create a > + * underutilized metadata chunk. So if this is our first run > + * through the flushing state machine skip ALLOC_CHUNK_FORCE and > + * commit the transaction. If nothing has changed the next go > + * around then we can force a chunk allocation. > + */ > + if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles) > + flush_state++; > + > if (flush_state > COMMIT_TRANS) { > commit_cycles++; > if (commit_cycles > 2) { > diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h > index 63d1f9d8b8c7..dd0e6f8d6b6e 100644 > --- a/include/trace/events/btrfs.h > +++ b/include/trace/events/btrfs.h > @@ -1051,6 +1051,7 @@ TRACE_EVENT(btrfs_trigger_flush, > { FLUSH_DELAYED_REFS_NR, "FLUSH_DELAYED_REFS_NR"}, \ > { FLUSH_DELAYED_REFS, "FLUSH_ELAYED_REFS"}, \ > { ALLOC_CHUNK, "ALLOC_CHUNK"}, \ > + { ALLOC_CHUNK_FORCE, "ALLOC_CHUNK_FORCE"}, \ > { COMMIT_TRANS, "COMMIT_TRANS"}) > > TRACE_EVENT(btrfs_flush_space, >