Re: git-svnimport failed and now git-repack hates me

From: Randal L. Schwartz <merlyn@stonehenge.com>
Date: Jan 4, 2007, 02:40 UTC
Message-ID: <86ps9vbjlp.fsf@blue.stonehenge.com>
In-Reply-To: <20070104023350.GA1194@localdomain>

>>>>> "Eric" == Eric Wong <normalperson@yhbt.net> writes:

Eric> Part of it is Perl, which (as far as I know) never frees allocated Eric> memory back to the OS (although Perl can reuse the allocated memory for Eric> other things).

It does on Linux, of all things. That's because Linux has a smarter malloc/free that uses mmap(2) for the large chunks. On Linux, Perl memory size can apparently grow and shrink nicely. The "old school" advice about Perl comes from sbrk(2)-driven malloc/free.

Try:

        $x[1e6] = "0";
        sleep 10; # do a ps here
        @x = ();
        sleep 30; # do a ps here

and watch the process on Linux. If I'm right, this should show a large process, then a smaller one.

If you're getting a growing process though, you probably have a circular data reference. Maybe you have a tree with backpointers, and those backpointers should have been weakened?

-- 
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