No, in many cases the JVM performance will match and sometimes even outperform a C++ implementation in terms of performance and I've seen a few examples of that

No, in many cases the JVM performance will match and sometimes even outperform a C++ implementation in terms of performance and I've seen a few examples of that, although math-heavy operations is usually not one of them. In terms of size and memory usage, a C++ implementation will almost always win. The problem with Java is that it's not as deterministic in terms of performance as C++, so in areas where that is a must, it has to be taken into account. Even after saying that, the GC can, and indeed should, be tweaked and optimized. The JVM gives you more tweaking options and tools to optimize the garbage collection than any other platform I've worked with, but most developers don't know about them or don't care. In cases like the original comment mentioned, it may have been better to continue using the C++ implementation, or it might have been useful to spend a bit less in consultants and developers and a bit on Azul's Zing (and maybe a few people that understood the platform). It might have saved a lot in the long term and indeed there are plenty of algorithmic trading solutions written in Java.