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 C5E9817BB1F for ; Wed, 3 Jul 2024 15:11:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720019512; cv=none; b=KaCpqeC0Azoj7yr9Ff2t19ETduaWx3ElTn5FudZrPNcsuXTlZt4sULGmDzgZnKEipIhwKeB2BQP+FCGVQPMZqBYSIHFnsA8w7I/wKXrJP0nNaaEUiBUjXC4A8IQc703n6FiX+HHoLOlY03/OOXTCKEZyYoA0JkrWXvBTNcTf3xY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720019512; c=relaxed/simple; bh=xAZ9w2mpL/pwgf60fpSD3rtvrzIEULXXErstpTmWRIg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=F/ltlKLLXq8ejtH2TYn1WqDPSvfDiWMLGc6m1xRlPCO3aIeXadDJZ5pBZpiyRey22s32YutfUzCKMBtybSRTXzSmoHXO3bXQDfSJgBEII8k022+uUXO79af2hxTjdFS/uQh29XU+ppBMfW86s7+GbeaYwXcYQbSwWSFrW9iDh8c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jT0upB7a; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="jT0upB7a" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 793FDC2BD10; Wed, 3 Jul 2024 15:11:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720019512; bh=xAZ9w2mpL/pwgf60fpSD3rtvrzIEULXXErstpTmWRIg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jT0upB7aM7rY9k+36DlCLTR3bC9PGoaWzuiGJBW8T9wqeXfUTRBG9vpQORRzapd/V S4WECOR5SwOm5S+laTdakQm3Uus+zKswuTnwjW9zb4Ufy81NPlr9hPchH1iiZM4ECL fNQXm3/RQ0e+DBnH4Zr+UwVxtQu6uaf3LV2bwoPpUhxBcJTZbuSOuvloNRvC1Gj9qG zxfHfYMJ+bNoQrml4QEYWvkw7kkkgVLv3b0SIV1R+VPeHByIXIBNpzHB3rhlbYcH56 OGszCcZsXpFSuC711hWDHMmhE1dYXk1E2HD9iHsOPSBExZcicLd/j9GEsEhM59RGZh Q0rq+qF4wpgbg== Date: Wed, 3 Jul 2024 11:11:51 -0400 From: Mike Snitzer To: Christoph Hellwig Cc: Chuck Lever III , Linux NFS Mailing List , Jeff Layton , Anna Schumaker , Trond Myklebust , Neil Brown , Dave Chinner Subject: Re: [PATCH v11 00/20] nfs/nfsd: add support for localio Message-ID: References: <20240702162831.91604-1-snitzer@kernel.org> <3A583EDC-519C-4820-87E9-F4DC164656DB@oracle.com> Precedence: bulk X-Mailing-List: linux-nfs@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 Wed, Jul 03, 2024 at 07:16:31AM -0700, Christoph Hellwig wrote: > On Wed, Jul 03, 2024 at 04:52:34AM -0400, Mike Snitzer wrote: > > Ultimately I simply wanted to keep momentum up, I'm sure you can > > relate to having a vision for phasing changes in without missing a > > cycle. But happy to just continue working it into the 6.12 > > development window. > > It just feels really rushed to have something with cross-subsystem > communication going in past -rc6 in a US holiday week. Sometimes > not rushing things too much will lead to much better results. Yes, I knew it to be very tight given the holiday. I should've just yielded to the reality of the calendar and there being some extra changes needed (remove "fake" svc_rqst in fs/nfsd/localio.c -- I was hopeful that could be done incrementally after merge but I digress). Will welcome any help you might offer to optimize localio as much as possible (doesn't need to be in near-term, whenever you might have time to look). Its current approach to use synchronous buffered read_iter and write_iter, with active waiting, should be improved. But Dave's idea to go full RMW to be page aligned will complicate a forecasted NFS roadmap item to allow for: "do-not-cache capabilities, so that the NFS server can turn off the buffer caching of files on clients (force O_DIRECT-like writing/reading)". But even that seems a catch-22 given the NFS client doesn't enforce DIO alignment.