In a pure compiled language, such as C, each variable gets compiled down to an offset in memory. (Although if you compile in debug mode, the variables are kept around for the debugger to correlate the memory to a name.)

In a virtual machine language, where new code can be brought in at any time during execution, such as Java or Perl, the variable names must be part of the object code somehow. This is to allow each module to access each others' variables (e.g., $File::Find::name). So, yes, there will be more memory taken up.

Is it "considerable"? In the grand scheme of things, no. In your example, it may be considerable, relatively speaking, but in most practical programs, the difference is quite minor. And since, in perl anyway, these are all kept in a global hash (of sorts), it doesn't really impact performance either.

Bottom line: this should not be a real concern for any practical software. I doubt that even a perl CGI script being called hundreds or thousands of times a second could improve performance or memory consumption noticeably by any ugly optimisation here.


In reply to Re: Does the size of a variable's name affect memory? by Tanktalus
in thread Does the size of a variable's name affect memory? by nmerriweather

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