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Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <1726980.McBZPkGeyK@silver> References: <1726980.McBZPkGeyK@silver> <20240129115512.1281624-1-dhowells@redhat.com> To: Christian Schoenebeck Cc: dhowells@redhat.com, Eric Van Hensbergen , Dominique Martinet , Latchesar Ionkov , Matthew Wilcox , Jeff Layton , Christian Brauner , netfs@lists.linux.dev, v9fs@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 0/3] 9p: Further netfslib-related changes Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <1400270.1706538135.1@warthog.procyon.org.uk> Content-Transfer-Encoding: quoted-printable Date: Mon, 29 Jan 2024 14:22:15 +0000 Message-ID: <1400271.1706538135@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.6 Christian Schoenebeck wrote: > > (1) Enable large folio support for 9p. This is handled entirely by > > netfslib and is already supported in afs. I wonder if we should = limit > > the maximum folio size to 1MiB to match the maximum I/O size in t= he 9p > > protocol. > = > The limit depends on user's 'msize' 9p client option and on the 9p trans= port > implementation. The hard limit with virtio transport for instance is cur= rently > just 500k (patches for virtio 4MB limit fetching dust unfortunately). Okay. Is that 500KiB or 512Kib? > Would you see an advantage to limit folio size? I mean p9_client_read() = etc. > are automatically limiting the read/write chunk size accordingly. For reads not so much, but for writes it would mean that a dirty folio is either entirely written or entirely failed. I don't know how important th= is would be for the 9p usecases. David