Re: [Rd] Build R with MKL and ICC

2015-09-09 Thread Nathan Kurz
As a short and simple approach, I just compiled the current R release on Ubuntu with ICC and MKL using just this: $ tar -xzf R-3.2.2.tar.gz $ cd R-3.2.2 $ CC=icc CXX=icpc AR=xiar LD=xild CFLAGS="-g -O3 -xHost" CXXFLAGS="-g -O3 -xHost" ./configure --with-blas="-lmkl_rt -lpthread" --with-lapack --en

[Rd] sample.int() algorithms

2015-09-09 Thread Nathan Kurz
I was experiencing a strange pattern of slowdowns when using sample.int(), where sampling from a one population would sometimes take 1000x longer than taking the same number of samples from a slightly larger population. For my application, this resulted in a runtime of several hours rather than

Re: [Rd] Build R with MKL and ICC

2015-09-29 Thread Nathan Kurz
arnaud gaboury wrote: > On Wed, Sep 9, 2015 at 11:26 PM, Nathan Kurz wrote: >> >> As a short and simple approach, I just compiled the current R release >> on Ubuntu with ICC and MKL using just this: >> >> $ tar -xzf R-3.2.2.tar.gz >> $ cd R-3.2.2 >> $ CC=

[Rd] Cost of garbage collection seems excessive

2015-01-09 Thread Nathan Kurz
When doing repeated regressions on large data sets, I'm finding that the time spent on garbage collection often exceeds the time spent on the regression itself. Consider this test program which I'm running on an Intel Haswell i7-4470 processor under Linux 3.13 using R 3.1.2 compiled with ICPC 14

Re: [Rd] Request to speed up save()

2015-01-15 Thread Nathan Kurz
On Thu, Jan 15, 2015 at 11:08 AM, Simon Urbanek wrote: > In addition to the major points that others made: if you care about speed, > don't use compression. With today's fast disks it's an order of magnitude > slower to use compression: > >> d=lapply(1:10, function(x) as.integer(rnorm(1e7))) >>

Re: [Rd] default min-v/nsize parameters

2015-01-17 Thread Nathan Kurz
On Thu, Jan 15, 2015 at 3:55 PM, Michael Lawrence wrote: > Just wanted to start a discussion on whether R could ship with more > appropriate GC parameters. I've been doing a number of similar measurements, and have come to the same conclusion. R is currently very conservative about memory usage,

Re: [Rd] [PATCH] Makefile: add support for git svn clones

2015-01-19 Thread Nathan Kurz
On Mon, Jan 19, 2015 at 1:00 PM, Felipe Balbi wrote: > I just thought that such a small patch which causes no visible change to > SVN users and allow for git users to build R would be acceptable, but if > it isn't, that's fine too. Felipe --- It would appear that you are unaware that you are wal

[Rd] Recycling memory with a small free list

2015-02-17 Thread Nathan Kurz
ormance improvement would be large. Measurement details are here: http://stackoverflow.com/questions/28532493/reusing-existing-memory-for-blas-operations-in-r Are there downsides or difficulties to this approach that I'm missing? Nathan Kurz n...@verse.com __

Re: [Rd] Recycling memory with a small free list

2015-02-18 Thread Nathan Kurz
On Wed, Feb 18, 2015 at 7:19 AM, Radford Neal wrote: >> ... with assignments inside of loops like this: >> >> reweight = function(iter, w, Q) { >> for (i in 1:iter) { >> wT = w * Q >> } >> } >> ... before the RHS is executed, the LHS allocation would be added >> to a small fixed length lis