Re: Memory consumption with cp -l (fwd)

[Ole Tange]

Oops. I sent this directly to Jim. It answers most of your questions.


/Ole
-- 
If some genie offered you three wishes, would not your first one be,
"Tell me, please, what is it that I want the most!"
  -- Marvin Minsky in
     freenet://address@hidden/truenames//

---------- Forwarded message ----------
Date: Mon, 10 Mar 2003 13:45:41 +0100 (CET)
From: Ole Tange <address@hidden>
To: Jim Meyering <address@hidden>
Subject: Re: Memory consumption with cp -l

On Mon, 10 Mar 2003, Jim Meyering wrote:

> > Is there any other thing that can influence on the RAM usage? E.g. version
> > of glibc, version of kernel, version of filesystem?
>
> Yes.
> Please tell me which ones you're using.
> Also, please include the version of gcc (assuming that's what
> you used) and a copy of the config.h file that was created
> in your 4.5.9 build directory.

Computer 1:

libc-2.2.4.so
Linux tigger.tange.dk 2.4.18 #10 SMP i686
ReiserFS version 3.6.25
$ gcc --version
3.0.1
$ cp --version
cp (fileutils) 4.1
$ cp-4.5.9 --version
cp (coreutils) 4.5.9


Computer 2:

libc-2.3.1.so
Linux medi.tange.dk 2.4.20-wolk4.0s-pre9 i686 P4 CPU 2.00GHz GNU/Linux
ReiserFS version 3.6.?
$ gcc --version
gcc (GCC) 3.2.1 20021207 (Gentoo Linux 3.2.1-20021207)
$ cp --version
cp (fileutils) 4.1.11
$ cp-4.5.9 --version
cp (coreutils) 4.5.9

I just retried with 'cp -a' and it seems I was mistaking: 'cp -a' does not
stay below 1 MB but eats approximately the same amount of RAM. This goes
for both version 4.1 and 4.5.9.

Actually I had a hard time reproducing the bug on Computer 2: When I
copied part of the original material the mem usage got large quickly. But
when I copied the copy the mem usage was fairly low. This got me thinking:
What is unique about the original? And there _is_ something unique: More
than 99% of the files have > 10 hardlinks. It seems _this_ is the cause.

You can reproduce the error by doing the following:

wget http://home.tange.dk/~tange/cp-bug/test-set.tgz
tar xfz test-set.tgz
cp-4.1 -Rl test-set t2     # Memusage: 18 MB for cp-4.1
cp-4.5.9 -Rl test-set t3   # Memusage: 5.9 MB for cp-4.5.9


/Ole
-- 
If some genie offered you three wishes, would not your first one be,
"Tell me, please, what is it that I want the most!"
  -- Marvin Minsky in
     freenet://address@hidden/truenames//