I haven't seen this convincingly demonstrated. Can you point to good examples? The few times I've seen concrete claims they are usually comparing Java code with C code that no performance oriented C programmer would actually write. In certain cases Java can allocate memory faster than generic malloc but in practice in many of those cases a competent C or C++ programmer would be using the stack or a custom bump allocator.

In practice it's quite hard to do really meaningful real world performance comparisons because real world code tends to be quite complex and expensive to port to another language in a way that is idiomatic. My general observation is that where performance really matters to the bottom line or where there is a real culture of high performance code C and C++ still dominate however. This is certainly true in the fields I have most experience in and where there are many very performance oriented programmers: games, graphics and VR.