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From: Dirkjan Ochtman <dirkjan@ochtman.nl>
Date: Thu, 30 Jun 2011 10:06:41 +0200
Message-ID: <BANLkTi=+hJEFo4XohonBvjTosFU3ZvxoCQ@mail.gmail.com>
Subject: Re: Has Erlang's promise of parallelism been realised in CouchDB?
To: user@couchdb.apache.org
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On Thu, Jun 30, 2011 at 09:53, Randall Leeds <randall.leeds@gmail.com> wrote:
> But beyond the parallelization of request handling there's concurrency
> in the more general sense. The neat thing about Erlang, and why it has
> its reputation, is that the CouchDB code can be liberal about its use
> of concurrency at the code level without suffering from deadlocks or
> other headaches that often plague programmers of complex,
> multi-threaded shared memory systems. The Erlang team has taken care
> of all the hard parts about sharing data in a concurrent environment.
> As I understand it, the Erlang runtime's use of chipsets with many
> hardware threads is only improving, and those benefits will be
> automatically conferred upon CouchDB.

One thing that, as far as I know, has not been parallellized is the
view indexer. While it should be possible to execute at least the map
part of map/reduce concurrently, CouchDB doesn't do that yet. IIRC
there were reasons for that? But at least it's good to be aware of.

Cheers,

Dirkjan