And most modern OSes can finagle bits in the page table to remove the need for copying.
That tends to be more trouble than it's worth. It usually means flushing caches, locking lots of things, and having to interrupt every CPU. Unless it's a really big data move (megabytes) it's probably a lose. Mach did that, and it didn't work out well.
That tends to be more trouble than it's worth. It usually means flushing caches, locking lots of things, and having to interrupt every CPU. Unless it's a really big data move (megabytes) it's probably a lose. Mach did that, and it didn't work out well.