Re: [Valgrind-users] Does anybody know about spacetime

[Zhou, J. \(Jack\) <zh...@al...>]

Hi,Nick,

Thanks for your response.
I skimmed the paper you referred in the mail. Is the spacetime from =
massif the sum of lag/use/drag/void spacetime or one or some of them?=20

Regards,
Jack

-----Original Message-----
From: Nicholas Nethercote [mailto:nj...@cs...]=20
Sent: 2007=C4=EA8=D4=C220=C8=D5 15:40
To: Zhou, Jie (Jack)
Cc: val...@li...
Subject: Re: [Valgrind-users] Does anybody know about spacetime

On Mon, 20 Aug 2007, Zhou, Jie (Jack) wrote:

> I am using Valgrind in a automatic testing tool. It's really powerful.
>
> Just one question about spacetime:
>
> Why is the output of massif tool designed in form of spacetime? How is
> the spacetime suppose to be used to evaluate a program's performance?
> All I care about is the space that the program occupy. Is there any
> possibility that I can get the memory(space) or relative memory rather
> than spacetime.
> Is there any paper or material that I can refer to?

Spacetime measurements came out of memory heap profilers for Haskell.  =
See=20
this paper for details:

@InProceedings{Roj:ldvu1996,
     author      =3D {Niklas R{\"o}jemo and Colin Runciman},
     title       =3D {Lag, drag, void and use -- heap profiling and
                    space-efficient compilation revisited},
     booktitle   =3D {Proceedings of the ACM SIGPLAN International =
Conference
                    on Functional Programming (ICFP '96)},
     pages       =3D {34--41},
     address     =3D {Philadelphia, Pennsylvania, USA},
     month       =3D jun,
     year        =3D 1996,
}

I implemented Massif to use the same approach.  However, it doesn't work =
as=20
well for programs in other languages -- Haskell's memory usage is quite=20
unusual due to its laziness.

For this reason, I'm partway through a rewrite of Massif.  You can check =
out=20
the branch holding it like this:

   svn co svn://svn.valgrind.org/valgrind/branches/MASSIF2

It's still experimental, but should give you an idea of what I'm aiming =
for.=20
I haven't had time to work on it recently, but hope to spend some time =
on it=20
soon.

Nick