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From: Damien Doligez <damien.doligez@inria.fr>
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Date: Wed, 4 Jan 2012 19:03:52 +0100
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To: Caml List <caml-list@inria.fr>
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Subject: Re: [Caml-list] Understanding usage by the runtime

On 2012-01-01, at 13:44, Richard W.M. Jones wrote:

> Is compaction disabled?  lablgtk disables it unconditionally by
> setting the global Gc max_overhead (see also the Gc documentation):
> 
>  src/gtkMain.ml:
>    let () = Gc.set {(Gc.get()) with Gc.max_overhead = 1000000}

Anyone who disables compaction should seriously consider switching
to the first-fit allocation policy:

  let () = Gc.set {(Gc.get ()) with Gc.allocation_policy = 1}

This may slow down allocations a bit, but the theory tells us that
it completely prevents unbounded fragmentation of the OCaml heap.

-- Damien