Return-Path: william@bourbon.usc.edu Delivery-Date: Mon Oct 6 10:49:52 2008 X-Spam-Checker-Version: SpamAssassin 3.2.3 (2007-08-08) on merlot.usc.edu X-Spam-Level: X-Spam-Status: No, score=-2.3 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=3.2.3 Received: from bourbon.usc.edu (bourbon.usc.edu [128.125.9.75]) by merlot.usc.edu (8.14.1/8.14.1) with ESMTP id m96HnpK7025389 for ; Mon, 6 Oct 2008 10:49:52 -0700 Received: from bourbon.usc.edu (localhost.localdomain [127.0.0.1]) by bourbon.usc.edu (8.14.2/8.14.1) with ESMTP id m96HtfA7024615 for ; Mon, 6 Oct 2008 10:55:41 -0700 Message-Id: <200810061755.m96HtfA7024615@bourbon.usc.edu> To: cs551@merlot.usc.edu Subject: Re: CS551 : Final project 1 Date: Mon, 06 Oct 2008 10:55:41 -0700 From: Bill Cheng Someone wrote: > In the design you mentioned each writing thread has an input queue of > its own and along with that there is a main queue which the event > dispatcher uses to direct requests to, is that right? Yes. -- Bill Cheng // bill.cheng@usc.edu On Mon, Oct 6, 2008 at 9:05 AM, Bill Cheng wrote: > I forgot to mention... This thread also acts as the > network-write thread in slide 19 of lecture 9. Therefore, > it needs to check its input queue to see if there is work > to do, i.e., data to send. > -- > Bill Cheng // bill.cheng@usc.edu > > > > -----Original Message----- > Date: Mon, 06 Oct 2008 08:42:21 -0700 > From: Bill Cheng > To: cs551@merlot.usc.edu > Subject: Re: CS551 : Final project 1 > > Someone wrote: > > > After the startup, every node will send hello to > > every neighbor node. What the node (the client part) will do after the > > startup?? Should it close the connection and exit the client thread?? > > If it close the connection then should it has to send notify message. > > > > Hello should be sent at the start up time or before initiating a data > > transfer?? > > > > If we have keepalive message then why we need hello? > > If you look at slide 14 of lecture 9, when you see that there > is a line drawn between two nodes, it means that there is an > *active* connection between the two nodes. > > If you close a connection, the link will be gone. > > On slide 19 of lecture 9, I have shown a design (just a > design and not "the" design) where two threads are used per > socket. It's perfectly fine to use one thread per socket, > like you are suggesting above. > > What does such a thread do? Well, this is a network. The > main job for a node in the network is to *forward* packets. > So, a thread would just wait for a packet to arrive, > decrement its TTL, and decide what to do with the packet. > > If you decide to bring down an active connection, you should > always send NOTIFY before you shutdown and close the socket. > -- > Bill Cheng // bill.cheng@usc.edu