From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=toxicpanda-com.20230601.gappssmtp.com header.i=@toxicpanda-com.20230601.gappssmtp.com header.b="pSWkUxVl" Received: from mail-yb1-xb33.google.com (mail-yb1-xb33.google.com [IPv6:2607:f8b0:4864:20::b33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2648B10CB for ; Tue, 21 Nov 2023 06:20:00 -0800 (PST) Received: by mail-yb1-xb33.google.com with SMTP id 3f1490d57ef6-daf7ed42ea6so5461464276.0 for ; Tue, 21 Nov 2023 06:20:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20230601.gappssmtp.com; s=20230601; t=1700576399; x=1701181199; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=3y23FWuz6PW8S0smY6WbbhGEXrCcP+R/szjSRN7aCT8=; b=pSWkUxVlXFRA34cTwHEW5S8dLdvaOlMauGOpQrsISGIIVVqn337RdkCOF1uqxE28D4 5q5J9sxipOmy203ltWSkS6XyIbSx7jKpMN67zeoqAG4/tch9bdZAUi/FN2Z6kxpCIk9B XTtRmPSe6pMEzSVIDVSgV09BSS0IT/5Qrlk1WTHI/8RqZxKJH8kbs7BILZPIRjik36jl XJFYpbvBVVcri5hGS6noJpeP307ZTKBDPcpZMfXUOpC9b/1cfCCcihGkXWnEj7CsTdGn 7CruFkgYfulRRt6G86cly53oAGbL298KViJo5zABeIXeP1gi/lx9ArRyFvsbRhRobZeR Bskg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700576399; x=1701181199; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=3y23FWuz6PW8S0smY6WbbhGEXrCcP+R/szjSRN7aCT8=; b=ZPZ4wIXQ8zoazujd7MvyyrGRnQm3VvXXP7g5ZBcp5ydxL3mZsNWJnTawCW5IdwRQa/ z+MKsMggVL/NvXeLxKO1FO5HpB3cd6+nQLhzxSVvgZ44aAnQ/qzTS+pTn8K47HdDGtSY 0u6SlOMhjoH53IV7wyfnXZN7V3VAn1RS5F+vU6lHM/ttifK3fAuNbx4WA0zMm03k76W1 Lr/Ig83XQ3UpjtZ4gARM3rGo80W7o2YbXdf59Lz1/LFxvvp/4MzmO4sF76GH3Z32+DJK bSEJt38Ij0F4upPtdL3cKMawrwhytualIhHLH56msGOBFkhbCanSAYSGHyWU3shN8Erb +c6w== X-Gm-Message-State: AOJu0YwFNv4n7N7TbNd4kjMX/KVbjheJXBH8TEsYpajhTOYcqdkUrEGh Jlf/QLOhw+cNkc6fiT/Tki2W84cFXRH3oIyo80mgcQNo X-Google-Smtp-Source: AGHT+IG5DWqsbXiH9pgFAk7q7UR5i7wyXZN3ItzEAQNEvuTk8K0wItke4fzX4RrSaX/85x7oSg2NnQ== X-Received: by 2002:a05:690c:2a85:b0:5b3:26e1:320c with SMTP id ek5-20020a05690c2a8500b005b326e1320cmr4372562ywb.40.1700576399323; Tue, 21 Nov 2023 06:19:59 -0800 (PST) Received: from localhost (cpe-76-182-20-124.nc.res.rr.com. [76.182.20.124]) by smtp.gmail.com with ESMTPSA id h4-20020a0df704000000b00559fb950d9fsm3033400ywf.45.2023.11.21.06.19.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Nov 2023 06:19:59 -0800 (PST) Date: Tue, 21 Nov 2023 09:19:58 -0500 From: Josef Bacik To: David Sterba Cc: linux-btrfs@vger.kernel.org Subject: Re: [PATCH 0/5] Reduce size of extent_io_tree, remove fs_info Message-ID: <20231121141958.GB1667963@perftesting> References: Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Nov 21, 2023 at 02:20:12PM +0100, David Sterba wrote: > We have the fs_info pointer in extent_io_tree for the trace points as > the inode is not always set. This is a bit wasteful and extent_io_tree > is also embedded in other structures. The tree owner can be used to > determine if the inode is expected to be non-NULL, otherwise we can > store the fs_info pointer. > > I tried to do it in the cleanest way, union and access wrappers, it's > IMO worth the space savings: > > - btrfs_inode 1104 -> 1088 > - btrfs_device 520 -> 512 > - btrfs_root 1360 -> 1344 > - btrfs_transaction 456 -> 440 > - btrfs_fs_info 3600 -> 3592 > - reloc_control 1520 -> 1512 > > The btrfs_inode structure is getting closer to the 1024 size where it > would pack better in the slab pages. > Reviewed-by: Josef Bacik Thanks, Josef