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by valenterry 1984 days ago
I mean, you are right that Akka Cluster is JVM based and hence can bring the problems you mentioned. But then again, most high frequency trading also runs on the JVM, so it can often be worked around.

> If this happens frequently enough (to affect say 5% of your users – enough to kill your game experience), is the benefits of latency gain from in-memory object reads wiped out?

For this specific use-case, I don't think there is really an alternative, except for specifically a hand-crafted system (or non-scale, such as everyone hosts and manages their own server).
1 comments
vinay_ys 1984 days ago
> But then again, most high frequency trading also runs on the JVM, so it can often be worked around.

JVM is an awesome piece of technology. And you can do robotic control systems to high-frequency trading systems with it with careful programming.

But I've seen a lot of Java code running in production suffering from latency jitters and needing continuous profiling and optimization by a small group of performance engineers while the majority of application engineers keep adding to GC load.

> For this specific use-case, I don't think there is really an alternative, except for specifically a hand-crafted system

Yes, but I think the handcrafted system doesn't need to be very complex. It can be quite simple and easy to understand and tame to your needs as your scale and complexity grows.

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randomopining 1983 days ago
Doesn't it have the new GC's that are supposed to be minimal pause and gamechangers?
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valenterry 1983 days ago
Yes, but for GC still must happen and sometimes even milliseconds can be a problem, depending on the use-case. It really depends on what your business does, so the OPs concerns with the JVM are very valid.

At the same time, I think (while not being an expert) that in the majority of the cases, the GC will not be a problem and that the time you can save from using Akka Cluster allows you to optimize your system more than enough to make up for any GC latency problems, in almost every system.

The only technology that might be better/comparable here is the erlang VM, but I have never used it myself.

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