Linked by kragil on Wed 23rd Jan 2013 20:26 UTC
Google "Native Client enables Chrome to run high-performance apps compiled from your C and C++ code. One of the main goals of Native Client is to be architecture-independent, so that all machines can run NaCl content. Today we're taking another step toward that goal: our Native Client SDK now supports ARM devices, from version 25 and onwards."
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RE[8]: Comment by Laurence
by Neolander on Thu 24th Jan 2013 13:47 UTC in reply to "RE[7]: Comment by Laurence"
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"That is also a problem with manual dynamic memory management, though, or any other form of system resource allocation for that matter. Whatever programming language you use, when writing high-performance code, you probably want to allocate as much as possible in advance, so as to avoid having to perform system calls of unpredictable latency within the "fast" snippets later."

Unless of course you're operating in the real world where resources are finite. Writing high-performance code is a balancing act between various opposing requirements and automatic GC takes that control away from you. It feeds you some of it back in the form of manual GC invocation, but often that is insufficient.

I agree that GC does take some control away, but can you provide some use cases as for when this is a problem ?

Also please note that you are totally strawmanning my position - I never said anything about manual dynamic memory control.

You said something about random latency bubles called by GC operation. I said that if you care about such, you should not use dynamic memory management at all, GC or not, since it is a source of extra latency on its own. How is that strawmanning ?

"Now, your problem seems to be that GC runtimes can seemingly decide to run an expensive GC cycle at the worst possible moment, long after objects have been apparently disposed of. But that's an avoidable outcome, since any serious garbage-collected programming language comes with a standard library function that manually triggers a GC cycle (runtime.GC() in Go, Runtime.gc() in Java, GC.Collect() in C#/.Net). The very reason which such functions exist is so that one can trigger GC overhead in a controlled fashion, in situations where it is not acceptable to endure it at an unpredictable point in the future."

Good luck with that in the odd interrupt handler routine. If your multi-threaded runtime suddenly decides, for whatever reason, that it is time to collect garbage, I'd enjoy watching you debug that odd system panic, locking loop, packet drop or latency bubble.

If you have GC'd away the initialization garbage before enabling the interrupt handler, and are not allocating tremendous amounts of RAM in the interrupt handler, why should the GC take a lot of time to execute, or even execute at all ?

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