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Impact of GC on memoized algorithm
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Date: -- (:)
From: Alexander S. Usov <A.S.Usov@K...>
Subject: Re: [Caml-list] Impact of GC on memoized algorithm
On Wednesday 30 March 2005 14:34, Alex Baretta wrote:
> > In this case, if you are using an inappropriate data structure as the key
> > to the hash table then you may be getting a lot of clashes. In which
> > case, lots of time will be spent looking up elements in hash table's own
> > list implementation. IIRC, most of the time will then be spent in the
> > Hashtbl.find_rec function...
>
> This is rather unlikely. The key to the hashtable is a unique integer...
>
> Rather, what happens, time-wise, if I create a hashtable with 4096 slots
> and end up filling it with several million key-value pairs?

In the best case you end up with a few hundreds or even few thousands of 
elements per bucket. And it will make it really slow.
You should better increase a hashtable size by at least an order of magnitude,
or create a hash of hashes.

-- 
Best regards,
  Alexander.