discuss-gnustep
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: back online again


From: Richard Frith-Macdonald
Subject: Re: back online again
Date: Sun, 15 Jan 2006 07:07:17 +0000


On 14 Jan 2006, at 23:52, Helge Hess wrote:

Richard Frith-Macdonald wrote:
I'd like to get GNUstep working properly in the 64bit environment ...
it seems to be considerably faster than the 32bit environment on the
same machine (I had expected it to be about 20% faster but it seemed
more like double the speed when I was compiling).

Do you have an idea why this is? I would expect a 64bit env to be quite
a bit _slower_ than a 32bit one for regular applications (<2GB memory
requirement, object oriented) due to the massively higher (ptr) memory
overhead and load times?

I think I  foolishly spoke much too soon and had the wrong impression.

Going back and doing the same things again I found no significant speed difference between the two environments, and after thinking about it a bit I now suspect that disk i/o is the main issue ... and I probably got the spurios impression of a major speed difference because I compiled the base library first in the 32bit environment (wheren everything had to be read from disk) and later in the 64bit environment the system already had everything it needed in memory.

Obviously we need well designed benchmarks run repeatedly rather than quick initial impressions of performance.

While the benchmark program in the base library can not be described as well designed or comprehensive etc ... I thought it might be interesting to run it anyway. It is at least a test of ObjC code perfomance without and disk I/O (other than loading the program itsself).

Unfortunately it was written for times when processors were much slower .. and takes only about 7 seconds to run ... but it would appear to show that the 64bit and 32bit code runs at pretty much the same speed. Repeatedly running the benchmarks I found that the 64bit code was consistently a little faster ... typically 7.03 seconds when the 32bit version took 7.32 seconds, but I doubt that the difference is really very meaningful.





reply via email to

[Prev in Thread] Current Thread [Next in Thread]