Throwing out some ideas at random:

• Make sure that your data is properly scoped.
• You say it's caching but do you clear unneeded data out after however long (so long as something has a reference to it things won't get garbage collected and will sit around)?
• Maybe rather than keeping things in RAM you might use MLDBM or Berkeley_DB and cache some or all of your data to disk instead. If you're caching to avoid recomputing something computationally expensive the hit for IO may be smaller that the tradeoff is still worth it
• Rewrite your program in C.
• Less drastically use memcache or redis or the like (a distributed key/value store) and its (hopefully) more memory efficient representation.

Update: Hrmm you mention Tokyo Cabinet in another reply above so that probably negates at least two of my suggestions. Probably the first join suggestion or using pack/unpack are going to be the way to go. You might also see if you can get an unpack incantation that will work with your TC arrays.

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.