Re^2: Share symbol table between threads

Basically, I am writing a RPC like server, it listen on IO::Socket, and then spawn new threads for each request.

1. The client then need to ``register'' itself on the server first, which a thread A on server should ``require'' the module.

2. The client then use the returned stub to call a method (through AUTOLOAD). A nother thread B on server should then make the actuall call.

Currently I can only put ``require'' and actual call both in thread B to load the module and let the symbol available.

What I tent to is load it once at thread A, so following methods calls won't repeately load it again.

I have also come up with an idea that by keeping my own shared HASH symbol table at the main thread, and use AUTOLOAD to point it when necessary. But will it achieveable? or would it make performance better? I don't know.

Thanks

Comment on Re^2: Share symbol table between threads

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Re^3: Share symbol table between threads by jbert (Priest) on Oct 04, 2006 at 12:26 UTC
Ah I get it. You're letting the threads die after handling a request and starting a new thread per request. If you're concerned about performance, the general advice is to have a persistent thread pool, with the number of threads proportional to the number of execution cores on your system. There appears to be a CPAN module, Thread::Pool which automates this process. If you did this, then you'll just require the modules in-thread and they'll only be loaded once per thread. Looking at the docs, you'll want max == min so that threads don't die off. There are performance tradeoffs here. Using a pool should reduce mean latency (since you don't have to start a new perl thread before handling the request) but may introduce unpredictably to the latency, since the pool may be at max when a new request comes in. An appropriately-sized pool should increase the throughput (ops/second) since less work is being done per op (you aren't starting a whole new thread).	[reply]
Re^4: Share symbol table between threads by jwu (Novice) on Oct 04, 2006 at 13:22 UTC
Thanks jbert, I will keep that in mind, but for now, I will choose the simple solution by ``require'' it every time. The principle of this module is to be simple. The whole module only in 200 lines (thanks for AUTOLOAD). I probably use Thread::Pool as a plugin later. By the way, the module will be on CPAN as RPC::Object (wait some time before it appears). Thanks for your help.	[reply]