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Subject: Re: [Boost-build] Parallel builds
From: K. Noel Belcourt (kbelco_at_[hidden])
Date: 2010-11-18 19:10:39

On Nov 18, 2010, at 4:28 PM, K. Noel Belcourt wrote:

> Hi,
> Generally I'm quite pleased with the parallel build throughput of
> bjam but lately I've noticed some latencies that I'd like to fix up
> (eliminate). The problem is on larger SMP machines with lengthy
> compile times (slower compilers). What happens is N compile jobs get
> started and most complete quickly though perhaps one or a few
> outliers run a long time or until they time out and are killed.

> A "feature" of the unix parallel build capability in bjam is that it
> won't spawn any new processes (actions) until the currently active
> processes complete

Oops, this is false. We do continuously spawn new processes. For
some reason on this one system, bjam seems to wait until all current
actions complete before launching N more actions.

  -- Noel

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