DBMs don't, in general, shrink. It's very difficult to give "this block" back to the O/S... only the blocks at the end. (Very similar in fact to the allocation of memory in traditional Unix.)

If you're concerned, you can simply create a new DBM. If you've got enough memory, pull the hash into memory, close the DBM, delete the files, and reopen it and re-store, like: 

dbmopen %FOO, "my_db", 0666 or die;
... populate %FOO
... delete some stuff from %FOO
{
  my %TEMP = %FOO; # cache it in memory
  dbmclose %FOO;
  unlink <my_db*>; # danger, but general enough {grin}
  dbmopen %FOO, "my_db", 0666 or die;
  %FOO = %TEMP;
}

[download]

-- Randal L. Schwartz, Perl hacker

In reply to Re: DBM problem by merlyn
in thread DBM problem by frechettes

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