On 01/05/2015 14:02, Mark Thomas wrote: > On 01/05/2015 13:42, Jess Holle wrote: >> Naively, looking at the Tomcat documentation and note the comparison >> table there makes it appear that: >> >> 1. NIO2 offers everything NIO does >> 2. NIO cannot offer true blocking IO, whereas NIO2 can >> >> If that's not true, then the documentation should be updated at least.... > > It depends how you define "true blocking IO". None of the three > connectors in trunk provide blocking I/O via a single read or write > call. For all of them you call read/write and then you need to call > something else that blocks until the read/write has finished. Only BIO > offered "true" blocking I/O in my view.
I take that back. APR does offer true blocking. Mark > I'll update the docs. > > Mark > > >> >> And, of course, NIO2 just sounds newer/better/fancier than NIO :-) >> >> On 5/1/2015 4:55 AM, Mark Thomas wrote: >>> Next up on my list is the NIO2 connector. >>> >>> NIO and APR/native both use a polling approach to non-blocking I/O. You >>> add the socket to the poller, tell it what operation (read/write) you >>> want to perform and then you wait for the poller to tell you the socket >>> is ready to perform that operation. >>> >>> NIO2 uses an asynchronous approach to non-blocking I/O. You perform the >>> read/write and then wait to be told it has finished via either a Future >>> or a CompletionHandler. >>> >>> Servlet 3.1 non-blocking I/O is closest to the polling style (you get a >>> callback when you are allowed to read/write). >>> >>> WebSocket non-blocking I/O uses the asynchronous style. >>> >>> In short, regardless of the underlying approach to non-blocking I/O, we >>> have to support JavaEE APIs that use both styles. Therefore there is no >>> 'obvious' advantage for either NIO or NIO2. >>> >>> As far as I can tell, the performance of NIO and NIO2 are comparable. >>> >>> That raises the question why do we need both NIO and NIO2? And I don't >>> have an answer to that. If I had to pick one, I'd pick NIO because: >>> - it has been around longer and is more stable >>> - it uses the same style as APR/native which may allow further >>> refactoring to reduce duplication. >>> >>> So, should we drop one of NIO or NIO2 in Tomcat 9? If not, why not? If >>> yes, which one? >>> >>> Mark >>> >>> --------------------------------------------------------------------- >>> To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org >>> For additional commands, e-mail: dev-h...@tomcat.apache.org >>> >>> >> >> > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org > For additional commands, e-mail: dev-h...@tomcat.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For additional commands, e-mail: dev-h...@tomcat.apache.org
