From: "Alexander S. Usov" <A.S.Usov@KVI.nl>
To: caml-list@yquem.inria.fr
Subject: Re: [Caml-list] Impact of GC on memoized algorithm
Date: Wed, 30 Mar 2005 15:09:01 +0200 [thread overview]
Message-ID: <200503301509.01571.A.S.Usov@kvi.nl> (raw)
In-Reply-To: <424A9CCA.7030204@barettadeit.com>
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.
next prev parent reply other threads:[~2005-03-30 13:09 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-03-30 8:39 Alex Baretta
2005-03-30 12:03 ` [Caml-list] " Jon Harrop
2005-03-30 12:34 ` Alex Baretta
2005-03-30 13:09 ` Alexander S. Usov [this message]
2005-03-30 13:56 ` Marcin 'Qrczak' Kowalczyk
2005-03-30 15:03 ` Alex Baretta
2005-03-31 14:41 ` Jean-Christophe Filliatre
2005-04-11 14:22 ` Damien Doligez
2005-04-11 15:48 ` Alex Baretta
2005-04-14 9:52 ` Damien Doligez
2005-04-14 10:27 ` Jan Kybic
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=200503301509.01571.A.S.Usov@kvi.nl \
--to=a.s.usov@kvi.nl \
--cc=caml-list@yquem.inria.fr \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).