3 ms·

So... Why exactly does it need 24 bytes if a long is only 8 bytes (64 bits)?

• kaushiks 10y ago
  For the 16 byte (on x86_64) header (markOop, klass *).
  • jcdavis 10y ago
    The header is only 12 bytes with compressedOops (which most people use), but the long is aligned on an 8 byte boundary so the advantage is wasted here.
    • alblue 10y ago
      And even if the long wasn't on an aligned boundary, the object itself is. So you either have padding at the start or end of the object.