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Impact of GC on memoized algorithm
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Date: 2005-03-30 (12:34)
From: Alex Baretta <alex@b...>
Subject: Re: [Caml-list] Impact of GC on memoized algorithm
Jon Harrop wrote:
> On Wednesday 30 March 2005 09:39, Alex Baretta wrote:
>>I have come to think that the difference in performance might be
>>attributable to the garbage collector.
> Try to objectively quantify the performance bottleneck using profiling, rather 
> than speculating. Most of the time, most of the people speculate 
> incorrectly. :-)

Might be. I'm just trying to analyze critically my own work.

> 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?


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