[troist]

I've used Java and C++ in a few low latency applications and I do prefer Java in certain scenarios. The whole ecosystem around Java makes rapid development easier meaning we could make safe changes quicker which is a big benefit in trading systems where you need to react to unpredictable market conditions.

The article focuses quite heavily on Zing vs Hotspot but it'd be interesting to see an analysis of a variety of the standard JVMs GC methods (namely Shenandoah).

For anyone interested in low latency Java I'd recommend watching some of Martin Thompson's talks on building LMAX and his blog Mechanical Sympathy is a great start too.

[oftenwrong]

>The article focuses quite heavily on Zing vs Hotspot but it'd be interesting to see an analysis of a variety of the standard JVMs GC methods (namely Shenandoah).

Also, ZGC, which is considered production-ready in JDK 15.

[bob1029]

LMAX Disruptor is a really powerful abstraction if you are trying to build something with consistently-low latency. I've been using a variant in .NET Core for purposes of processing UI events.

[secondcoming]

It was very interesting, I ported it to C++. However, I lost interest when the whole thing could lock up if the RingBuffer size was very small yet still a power of two.

It also uses sun.misc.Unsafe to do the latency critical aspects, so yes it's Java, but most certainly not vanilla Java.

[pron]

ZGC is at 1-2ms max pause time in JDK 16 and is expected to reach <1ms max pause time within a year.

[ISL]

Isn't this architecture dependent?

It is hard to imagine the same performance on a Pentium Pro.

What is the right processor-independent measure for latencies like this? Number of clock-ticks? That seems flawed, too.

[rokobobo]

I come from a place that used Java as the main language for its strategies, and the developers' overall sentiment was very close to yours.

I saw people comment on the "fast<->smart" continuum, and in this context, I believe they mean smart=computationally intensive. (An extreme example is a stat arb shop running its portfolio optimizer.) But there's another way to gain an edge, which is to iterate quickly on your "fast" algorithms and develop them so they take advantage of opportunities that are only partially exploited by competitors. Java seemed pretty good for that purpose for about a decade. Things like JVM warmup, GC, individual ultra-low-latency responses whenever necessary, were all dealt with after the fact.

[blibble]

where I've worked you avoid triggering the GC by making sure you have enough memory for the entire day's operations

with a modern JVM you can even disable it entirely (Epsilon collector)

[tormeh]

If you want something that's as fast as C++, but safer to work with, then there's this new language, has been on HN frontpage once or twice.. I can't remember the name, but I think it had something to do with oxidation of metals.. Something about shellfish as well..

[fractionalhare]

The person you're replying to is almost certainly not using the word "safe" in the same sense you are. In particular: safety in trading has to do with risk management, strategy correlation, side effects, and correctness.

Software security matters, in the abstract, but trading firms don't care about it nearly as much as tech companies do. The other thing is that being as fast as C++ is not compelling enough a reason to replace C++ for their use cases. If anything, Rust's dependency management story would be the thing to highlight (this is part of what's compelling about the JVM).

[pjmlp]

A language that brings the Gentoo installation experience to external libraries and requires special purpose data structures to compile properly?

[troebr]

I was surprised there was no mention of it in the article. Maybe it's not used commonly in the trading space?

[alexeiz]

A language that should not be named.