[R-SIG-Mac] performance difference GUI vs. terminal

[joerg van den hoff]

hi all,

I upgraded today from 2.0 to 2.1.0a on my G5.
I'm using still mostly the command line interface to R, but of course
the GUI is attractive, too, and better access to the quartz() device is 
a big plus (I would of course say a BIG thank you to the people who are 
engaged in this).

but (as I already noted  under 2.0) there is a rather big difference in 
performance when initiating the same calculations in the GUI and the 
terminal, respectively.

for instance, in the GUI I get:

 > date(); sum <- 0; for (i in 1:1000000) sum <- sum+i; date()
[1] "Thu May 19 13:46:24 2005"
[1] "Thu May 19 13:46:36 2005"
 >
i.e. about 12 sec. runtime


and doing the same in the terminal yields:

 > date(); sum <- 0; for (i in 1:1000000) sum <- sum+i; date()
[1] "Thu May 19 13:47:39 2005"
[1] "Thu May 19 13:47:42 2005"
 >

i.e. about 3 sec.(sometimes 2, have not timed it more accurately as with 
'date') runtime


give and take a second, it runs a factor of approx. 4-5 faster. why is 
this? what I note is that the G5 apparently does heavily access the HD, 
when calculations are under way from within the GUI. I don't see any 
reason for this (lots of free RAM etc.).

Have I missed something on the mailing list?

best regards,

joerg

PS: to be specific, this is

platform powerpc-apple-darwin7.9.0
arch     powerpc
os       darwin7.9.0
system   powerpc, darwin7.9.0
status   Patched
major    2
minor    1.0
year     2005
month    05
day      12
language R

under macos 10.3.9