From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F3EC187B for ; Tue, 28 Nov 2023 01:44:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="kfJKmt3U" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D17C6C433C7; Tue, 28 Nov 2023 01:44:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701135877; bh=eWvtaldwxSaw1rl6Txz8ZhPNrST2lh3prjRORUz+Zec=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kfJKmt3Ude1DoATKLzpVBVa0n/bw1vh7BISAV8tmEctZvOYjsBaqqMS6k8uZ91GdZ 9juOqnrqyNxj36mRuzctVb/LszcXESyZWT18a9qXy12pqqjsi39xR9vEXoiydPpwEl y2jv37DC4UOuJavlXnExCS45TrJ85mqX53GTVW+f8zxejmt1PRIvvXel02gWV2EAF/ U3f+1nURcyIQXXEWoVVbO5RQZZBtUMxSwK57LOGS4hxutE5w7nQzPTJnERwrTYl5y4 O2K3fBJ96JJFZLz0KBWfB/bYyKZDPnVScdrZ2HIcDEaZPHCYaO6+duLBFG+djL7iQf v/JTccWr+6YyQ== Date: Mon, 27 Nov 2023 17:44:37 -0800 From: "Darrick J. Wong" To: Christoph Hellwig Cc: linux-xfs@vger.kernel.org Subject: Re: [PATCH 2/4] xfs: add debug knobs to control btree bulk load slack factors Message-ID: <20231128014437.GN2766956@frogsfrogsfrogs> References: <170086926569.2770816.7549813820649168963.stgit@frogsfrogsfrogs> <170086926609.2770816.18279950636495716216.stgit@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-xfs@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 Fri, Nov 24, 2023 at 09:50:23PM -0800, Christoph Hellwig wrote: > On Fri, Nov 24, 2023 at 03:49:15PM -0800, Darrick J. Wong wrote: > > From: Darrick J. Wong > > > > Add some debug knobs so that we can control the leaf and node block > > slack when rebuilding btrees. > > Maybe expand a bit on what these "debug knows" are useful for and how > they work? They're not generally useful for users, obviously. For developers, it might be useful to construct btrees of various heights by crafting a filesystem with a certain number of records and then using repair+knobs to rebuild the index with a certain shape. Practically speaking, you'd only ever do that for extreme stress testing. --D