Question

I have several classes that suffer from cache contention and are allocated with the “new” operator. Can I somehow make sure that “new” returns an address aligned to a cache line?

I am using GCC (if it’s not portably possible).

Answer 1

You can use placement new to construct an object into a given region of memory:

  // Instantiate object into a pre-allocated buffer
  obj = new (buf) TheClass();

To get an aligned buffer buf, you can use memalign, sbrk or mmap.