From: "Lever, Charles" Subject: RE: ~800 mountpoint limitation Date: Fri, 17 Oct 2003 08:09:56 -0700 Sender: nfs-admin@lists.sourceforge.net Message-ID: <482A3FA0050D21419C269D13989C6113127F56@lavender-fe.eng.netapp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: Return-path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Cipher TLSv1:DES-CBC3-SHA:168) (Exim 3.31-VA-mm2 #1 (Debian)) id 1AAWFb-00012g-00 for ; Fri, 17 Oct 2003 08:10:47 -0700 Received: from mx01.netapp.com ([198.95.226.53]) by sc8-sf-mx1.sourceforge.net with esmtp (Exim 4.22) id 1AAWFX-0002Jj-L5 for nfs@lists.sourceforge.net; Fri, 17 Oct 2003 08:10:43 -0700 To: "Trond Myklebust" Errors-To: nfs-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Id: Discussion of NFS under Linux development, interoperability, and testing. List-Unsubscribe: , List-Archive: > The main point with putting all the transport to a given server on one > socket is that the UDP/TCP congestion control algorithms can then > function efficiently. Instead of competing against other packets > originating from itself, the client only has to deal with competition > from other clients. i guess i would buy that if someone could convince me the RPC client would actually do fair load balancing if given the opportunity. my own experience with multi process workloads is that we aren't there yet. in other words, TCP is *designed* to handle network contention, so i don't have a problem letting multiple sockets from the same client duke it out for network bandwidth. i also have some SMP scalability concerns. using a single transport means we have many processes on several CPUs that are contending for the socket buffer space, the socket and xprt locks, and that are holding the BKL while issuing RPCs. i know that NFSv4 is designed to work with a single connection to a server... so this is coming whether i like it or not :^) i hope we can arrive at a design that addresses the NFSv4 requirements and increases the per-client mount limit substantially, but does not suffer from the scalability issues i have raised. ------------------------------------------------------- This SF.net email sponsored by: Enterprise Linux Forum Conference & Expo The Event For Linux Datacenter Solutions & Strategies in The Enterprise Linux in the Boardroom; in the Front Office; & in the Server Room http://www.enterpriselinuxforum.com _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs