From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 95CAC56759 for ; Sat, 11 May 2024 15:59:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715443144; cv=none; b=tDCsjoq59VbFeXp6x/pUPawLcrW0xgfNdPXTNelg3z0hJy+S8DHU+zblxeTRWV9iv7rvxFKMswUg92MTIAetFg/WjU5ZzxRhpPFWAsCI3j3na+60dY+U/EZp/TaBRHAyre/LQDBVbsjMYIK4rodmYEGTqjO+9l/1TqBFTrJizyQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715443144; c=relaxed/simple; bh=osrocCXmUNVWie8FlSiyQRe6jjKRwqnpAxJarnfK1q8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=RQwd88sog0tjEu90Pkqj4T+CqUB8gnWZ+vpDUhmqRgKY0ZHb/QxDneSuY3r29DIZS3dEQH4ZFxBYMd0XczUlgRqgOnqGQ//F0AqAQhVxiASSk6dKXMJ99w07DDhdhwaQMNwPh+R1c8we3pfUGqqUS3nV/0oGjzT93rwrQwbNF8E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=AIOfS7zl; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="AIOfS7zl" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=OZQbE3XQNmN4pJYb6MLugF+03DmcuANWaIMZ5MvlqXc=; b=AIOfS7zlQyUDj9IS8Z2PTS0ZKA 2ilUqqA2kZlnlMLsM9ctQExU8+TjAI923Wv7/J1d6bGNhD6goJcrPdnwGqmDzak6sovJ/Q1CP7Dxo eaRdRGL21BjNChJaw0UPBLWuYbG3kwwP9j3ojKlRfINYcwvOxzD4myjjdkGjCzRc7I9442iWt8Xsr 1ndOWln/0XK7eFrU+RYz5SeKBmsXaCxN8niKIbcz/DsqCUJniRpDJoaAsnWXLa4/YHbCZhsMmkx0P jn00NzBMYSXVSIbbu8M6H+OBrt2U1mm2vCMcVxIPJ+oCUxL6yrECfksDDhUWNLgh1Ih8fXxhDyvxu MGc2xHbw==; Received: from willy by casper.infradead.org with local (Exim 4.97.1 #2 (Red Hat Linux)) id 1s5p7c-00000005cQg-3X45; Sat, 11 May 2024 15:58:52 +0000 Date: Sat, 11 May 2024 16:58:52 +0100 From: Matthew Wilcox To: Waiman Long Cc: Yafang Shao , Linus Torvalds , viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, linux-fsdevel@vger.kernel.org, Wangkai , Colin Walters Subject: Re: [RFC PATCH] fs: dcache: Delete the associated dentry when deleting a file Message-ID: References: <20240511022729.35144-1-laoar.shao@gmail.com> Precedence: bulk X-Mailing-List: linux-fsdevel@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 Sat, May 11, 2024 at 12:54:18AM -0400, Waiman Long wrote: > I had suggested in the past to have a sysctl parameter to set a threshold on > how many negative dentries (as a percentage of total system memory) are Yes, but that's obviously bogus. System memory is completely uncorrelated with the optimum number of negative dentries to keep around for workload performance. Some multiple of "number of positive dentries" might make sense.