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Re: How to burn 100 megabytes in one line and still get the wrong answer

by flyingmoose (Priest)
on May 17, 2004 at 16:43 UTC ( [id://354029]=note: print w/replies, xml ) Need Help??


in reply to How to burn 100 megabytes in one line and still get the wrong answer

C:\WINNT>perl -e "print 00x888888888;"
Out of memory!

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Amazing, it returns really quickly. Anyone care to speculate why this dies in a split second? Is the memory management engine really that smart? I didn't think Perl had any self-imposed ulimits or anything like that, and the Windows/Linux behavior is identical. You'd think it would slurp all available memory, but it looks like it doesn't even get close to trying.

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Re: Re: How to burn 100 megabytes in one line and still get the wrong answer
by Ven'Tatsu (Deacon) on May 17, 2004 at 17:12 UTC
    I belive perl will see the 'x' operator and try to allocate the necessary memory in one block. The OS will quickly not find a memory range large enough and fail the request, prompting perl to die. The alternative that would cause perl to die slowly would be if 'x' allocated a small string, copied it's first parameter into it until it ran out of space, then allocated a slightly larger sting, copied the old sting in, de-allocate the old sting, then continued to copy the first parameter until it ran out of room again. But that would be horribly inefficient. (even for perl =)
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