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From: David Kastrup <dak@gnu.org>
To: Eric Wong <normalperson@yhbt.net>
Cc: Niluge kiwi <kiwiiii@gmail.com>, git@vger.kernel.org
Subject: Re: git-svn metadata commands performance issue
Date: Thu, 15 Jan 2015 12:53:38 +0100	[thread overview]
Message-ID: <87sifcdzul.fsf@fencepost.gnu.org> (raw)
In-Reply-To: <20150114203012.GA26023@dcvr.yhbt.net> (Eric Wong's message of "Wed, 14 Jan 2015 20:30:12 +0000")

Eric Wong <normalperson@yhbt.net> writes:

> How big is the parent process which forks the git commands?  On Linux at
> least, fork() performance is negatively impacted by parent process
> memory size.

Huh.  I thought with the advent of demand-paging, at the very least with
copy-on-write, this was supposed to be sort of a non-issue.

The old original UNIX version, in contrast, consisted of swapping out
the current process without removing the in-memory copy.  But since the
in-memory copy then did the exec call and since usually the exec call
was happy about every page of free memory (we _are_ talking about
something like 64kB of total available memory here), that tended to work
reasonably well.

-- 
David Kastrup

      parent reply	other threads:[~2015-01-15 11:54 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-13 10:14 git-svn metadata commands performance issue Niluge kiwi
2015-01-14 20:30 ` Eric Wong
2015-01-15 10:14   ` [PATCH] git-svn: lazy load some modules Eric Wong
2015-01-15 11:26   ` git-svn metadata commands performance issue Niluge kiwi
2015-01-15 11:53   ` David Kastrup [this message]

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