Memory access time is measured in nanoseconds. Disk access time is measured in milliseconds. You will inevitably get a slowdown measured in orders of magnitude when you tie to disk.

There are 3 basic approaches:

  1. Buy more memory - probably cheaper than recoding - and leave your hash in memory.
  2. Improve your algorithm to be more efficient. Do you really need (all) that hash?
  3. Move the data to an RDBMS which is designed to efficiently index and manipulate large quantities of data.

Which approach works best for you depends on what it is you (think) you need the hash for. If you provide more details of the precise problem you are trying to solve then you will probably get a few useful algorithmic suggestions. Why is loading time an issue - is this a dynamic CGI/Tk type app? How much memory have you got? OS? Version of Perl?

cheers

tachyon

In reply to Re: Speeding a disk based hash by tachyon
in thread Speeding a disk based hash by albert

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