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Whoop! Multithreaded javascript with V8 JavaScript engine!

• apendleton 14y ago
  I can't actually find any details about how this works in practice. Are multiple maps and reduces in a map-reduce executed simultaneously within a single mongod process? If so, how many? Is it based on the number of cores in the server? Edit: not asking you specifically, just generally curious.
  • tbrock 14y ago
    Each map reduce job can still only use one thread. Before, under spider monkey, only one job could be executed per mongod instance. Now you can have many jobs executing in parallel on a single server instance but each one of them still only uses a single core.
    • apendleton 14y ago
      Do you know if this is likely to be permanent? In an application I work on, I do map-reduces on Mongo data using a third-party framework at the moment specifically to work around the inability to easily parallelize map-reduce jobs on a single machine.