XNIO Concepts: Difference between revisions

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=NIO Concepts=
=NIO Concepts=


* [[NIO Concepts#ByteBuffer|NIO ByteBuffer]]
* [[Java_Non-Blocking_I/O_Concepts#ByteBuffer|NIO ByteBuffer]]
* [[Java_Non-Blocking_I/O_Concepts#Channel|NIO Channel]]


=XNIO Worker=
=XNIO Worker=
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* '''Read threads''' that can handle callbacks for read events.
* '''Read threads''' that can handle callbacks for read events.
* '''Write threads''' that can handle callback for write events.
* '''Write threads''' that can handle callback for write events.
For details on how to configure I/O Threads see [[XNIO Configuration#WORKER_IO_THREADS|XNIO Configuration]].


==Worker Thread==
==Worker Thread==


Worker threads are used for blocking tasks (such as servlet invocations). The worker threads are managed by a standard Executor-based thread pool.
Worker threads are used for blocking tasks (such as servlet invocations). The worker threads are managed by a standard Executor-based thread pool.
For details on how to configure worker threads see [[XNIO Configuration#WORKER_TASK_CORE_THREADS|XNIO Configuration]].


=Channel=
=Channel=
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XNIO provides a channel abstraction that hides the underlying transport. Channels are notified of events using the <tt>ChannelListener</tt> API. Upon creation, channels are assigned an [[#I.2FO_Thread|I/O Thread]], which will be used to execute all <tt>ChannelListener</tt> invocations for the channel.
XNIO provides a channel abstraction that hides the underlying transport. Channels are notified of events using the <tt>ChannelListener</tt> API. Upon creation, channels are assigned an [[#I.2FO_Thread|I/O Thread]], which will be used to execute all <tt>ChannelListener</tt> invocations for the channel.


=Listener=
Also see [[NIO Concepts#Channel|NIO Channel]].
 
=ChannelListener=
 
A <tt>ChannelListener</tt> is a listener for [[#Channel|Channel]] events, such as: channel readable, channel writable, channel opened, channel closed, channel bound, channel unbound.

Latest revision as of 22:51, 25 July 2018

Internal

Overview

XNIO is a simplified low-level I/O layer, built in top of Java NIO. It has an API for combining blocking and non-blocking operations, even on the same channel.

NIO Concepts

XNIO Worker

An XNIO worker is the central point of coordination for a network application. It manages several kind of threads, and the threads created by the worker are tagged with the worker name. A worker has two different types of thread pools:

I/O Thread

The I/O threads run non-blocking handlers. They run in a loop, which does three things:

  1. runs any tasks that have been scheduled for execution by the I/O thread
  2. runs any scheduled tasks that have hit their timeout
  3. call Selector.start() and then invoke any callbacks for the selected keys.

The I/O must never perform blocking operations because they are responsible for multiple connections, so while the operation is blocking, the other connections will essentially hang.

The I/O threads come in two types:

  • Read threads that can handle callbacks for read events.
  • Write threads that can handle callback for write events.

For details on how to configure I/O Threads see XNIO Configuration.

Worker Thread

Worker threads are used for blocking tasks (such as servlet invocations). The worker threads are managed by a standard Executor-based thread pool.

For details on how to configure worker threads see XNIO Configuration.

Channel

XNIO provides a channel abstraction that hides the underlying transport. Channels are notified of events using the ChannelListener API. Upon creation, channels are assigned an I/O Thread, which will be used to execute all ChannelListener invocations for the channel.

Also see NIO Channel.

ChannelListener

A ChannelListener is a listener for Channel events, such as: channel readable, channel writable, channel opened, channel closed, channel bound, channel unbound.