And here is a speedy reply to the perlbug by Gisle Aas:

This is not a memory leak.  The reason perl allocates memory during 
printing is that it converts all the 0 values in the hashes to strings
+ 
and stores these.  This upgrades your SvIV structs containing 0 into 
the much larger SvPV structs containing both 0 and "0" (see [1]). 

--Gisle 

[1] http://search.cpan.org/src/GAAS/illguts-0.09/index.html#sviv

[download]

I won't claim to fully understand, but I guess it means that Perl is changing the hash from storing simply integers to storing both integers & strings during printing. And this change occurs on the hash itself, increasing memory usage. Printing without string interpolation (or join prevents this "upgrading" and thus prevents all the memory usage. I guess it makes sense, but I'm just really surprised no one had come across this before!

In reply to Re: Memory Error Printing Multiple Hashes Simultaneously by bernanke01
in thread Memory Error Printing Multiple Hashes Simultaneously by bernanke01

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