Hacker News Reader

Comment by kaba0 | Hacker News Reader

Latency and throughput are fundamentally opposite ends of the same axis. And perhaps the majority of Java applications prefer better throughput.

View on HN

But the graph in the article shows that ZGC now gets better throughput than G1! [EDIT no it doesn't]

I suspect the answer is that ZGC is not considered mature enough, and has a higher memory overhead than G1.

There are also other GCs that are heavily competitive with ZGC, such as Shenandoah. It might make sense to see how they all pan out before choosing a new default.

Shenandoah isn't an Oracle maintained feature, so they'll never allow it to become the OpenJDK default (though another vendor make it so in their distribution).

No, that graph may be hard to understand. It shows the relative improvement each GC has made since Java 8, not the absolute performance.

Ah, i realised it was relative, but i had assumed they were all relative to the same baseline! Should have been obvious from the way the bars are all level for JDK 8, really. That seems a needlessly unhelpful graph.

They are essentially 3 graphs displayed together. It probably would have make sense to present them more separately.

The article does not compare the throughput of different GCs other than different improvements. The baseline for the G1 graph is JDK8 G1 performance and the baseline for the ZGC graph is JDK11 ZGC performance. There is really nothing that can be directly compared between the two.

Reply on news.ycombinator.com