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javasocketsnio

What is the maximum number of channels that a selector can select?

I want to know how many channels can a selector can handle at maximum? I'm familiar with common I/O algorithms, but I don't know in NIO whether I can use a selector for handling (for example) 10000 sockets. Should use a number of threads and have a selector in each for handling a specific number of sockets?

While I found this, it didn't address this specific question.

Solution

  • There is no limit other than the number of socket descriptors. Some platforms have underlying limits, but NIO works around them with multiple OS selectors per Selector.

    There was a limit up to about Java 1.4.1 but it's long gone.

    Should use a number of threads and have a selector in each for handling a specific number of sockets?

    It's possible, but I don't really see why you should. Maybe the peers might get more regular service that way, it depends what your code has to do with every request.