From ripley at stats.ox.ac.uk  Sun Sep  6 18:12:21 2009
From: ripley at stats.ox.ac.uk (Prof Brian Ripley)
Date: Sun, 6 Sep 2009 17:12:21 +0100 (BST)
Subject: [Rd] question about --with-valgrind-instrumentation=level
In-Reply-To: <20090906160204.GA9440@stat.umn.edu>
References: <mailman.9.1252231204.24560.r-devel@r-project.org>
	<20090906160204.GA9440@stat.umn.edu>
Message-ID: <alpine.LFD.2.00.0909061707150.20763@gannet.stats.ox.ac.uk>

On Sun, 6 Sep 2009, Charles Geyer wrote:

> Does --with-valgrind-instrumentation=2 slow down R when valgrind or gctorture
> are not in use?  I am thinking of compiling the R that the whole department
> uses for research and teachin with --with-valgrind-instrumentation=2.  Is
> that a good idea or a bad idea?

It is a slightly bad idea: it does add extra code in memory.c that 
would always be called.

This only affects R.bin (or libR.so if you use the already slower 
shared-library version), so you can so as I do and simply use a 
different version of R.bin.

There is a similar issue with memory profiling.

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595



[Rd] question about --with-valgrind-instrumentation=level
Prof Brian Ripley