4 ms·

What would be the point of being able to spill to disk if you've got to keep everything in RAM? Simple serialization?

• nostrademons 16y ago
  The point is zero-copy on load, not being able to spill to disk. Most high-performance, scalable servers I've seen ignore virtual memory entirely and kill (+ restart) the process if it exceeds the physical memory available on the machine. Yes, that means they use pre-1960s technology; sometimes, the price of performance is ignoring the programming conveniences we've come up with in the last 50 years.
  • rbranson 16y ago
    Most applications need to perform some computations with data that is read from the backing store. Even simple sorts and searches will vastly outweigh the cost of an extra memcpy. Honestly, an HTTP cache is sort of a perfect case for the way in which Varnish was implemented. There is very little actual processing, if any, that needs to be done with the data that's read from disk. It just needs to be read from the backing store and shuttled over the socket as fast as possible, with very little friction. An extra memcpy or two matter in the Varnish scenario.