On Tue, 2013-01-15 at 13:29 +0000, Mark Thomas wrote: > Hi, > > I think I am going to need to refactor the APR Poller code. Before I get > to far down that road I wanted to get a sanity check from those that > understand the APR/native connector better than I do. > > The main problem: > - I need to be able to update the flags for a socket current in the > poller. For example, adding FLAGS_WRITE to a socket that currently has > FLAGS_READ > > Side issues: > - APR connections don't track number of HTTP keep-alives left (it gets > reset every time the socket goes back to the Poller) > - Currently we have two completely separate sets of Pollers. Once for > Comet and one for non-Comet. > > The reasoning for the refactoring: > > 1. Sockets should only be added to a pollset once. > 2. Because of 1) to update the flags the socket needs to be removed from > the pollset and re-added with the new flags. > 3. Currently, we have no record of which Poller a socket is registered > with. This makes 2) more expensive as we have to iterate through the > Pollers to find the socket. Tracking the current poller used by a socket > would make 2) a cheaper operation. > 4. Implementing 3) requires maintaining a mapping from socket to > SocketWrapper (like KeyAttachment does in NIO) > 5. A simple Map of Socket->SocketWrapper should give us what we need.
I had to solve each of these issues in the web container of JBoss. Although this is not going to be quite 100% compatible with Tomcat, it is very similar. I recommend looking at the branch that is in AS 7 trunk: http://anonsvn.jboss.org/repos/jbossweb/branches/7.2.x/ > In addition to enabling me to continue with the Servlet 3.1 NIO work, > the other advantages to the proposed refactoring are: > - Will be able to eliminate the CometPollers since the SocketWrapper > knows if a request is Comet or not. > - Proper tracking of HTTP keep-alive requests left per connection. > > If anyone can see a good reason not to start down this path, please > speak up. With APR, I would keep a separate poller for events (called comet in Tomcat) and keepalive, the code is rather different. Rémy --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For additional commands, e-mail: dev-h...@tomcat.apache.org
