On Sun, 13 Apr 2003, Aryan Ameri wrote: > A couple of months ago I bought a ThinkPad A 31, it's one of IBM's > high end models, with a 1.8 Ghz Pentium4 M, and 256 MB of DDR RAM. > However I am not quite happy with the performance that I am getting > out of this system.
Welcome to the Pentium-4, SpeedStep and slow, slow hard drives. :) > The system's performance can't even compete with my desktop system, > which is a Pentium III 600 Mhz with 128 MB SDRAM. This is my first > notebook computer, before this I never owned a notebook, so I don't > know, weather it is common for laptops to be so slow or not. Sure. The most likely problems are: 1. SpeedStep has your CPU running at 1.2GHz, not 1.8. To fix this, get a recent kernel with cpufreq support, enable SpeedStep as the driver and have something frob the public interface (/proc in 2.4, /sys in recent 2.5) to get 'performance' mode. You should be able to check this with the content of /proc/cpuinfo; mine shows the two speeds correctly (1.2 vs 1.7) of my A31p. 2. The Pentium-4 itself. The P4, even with the vastly improved core and cache in recent models, is a bit of a mixed bag when it comes to performance. This is compounded by the relative difference between RAM speed and the small cache on the mobile P4. So, in my experience, a 1.4GHz P3 will out-perform my 1.7 P4 running Emacs Lisp stuff and feel a bit snappier when doing desktop stuff. It's not much slower, in any sort of benchmark, just in "feel", though. OTOH, my P4 performs almost 40% better than the P3 doing MPEG-2 video encoding and runs modern 3d games a bit better under Windows than a P3 does... Sadly, you can only get used to these oddities of performance. Well, that, or you can sell the machine and get a P3 or Athlon based laptop instead. ;) 3. The slow, slow laptop hard drive. You got a good hard drive with your IBM laptop. It spins at 5400RPM, not 4200, and has a pretty low seek time all things considered. This is a fine and happy thing, but it's almost 30% slower than a slow desktop hard drive. Depending on your kernel, this can hurt quite a bit, because seek time always dominates performance and, sadly, 2.4 is pretty bad at handling disk access. 2.5.66+ are better, a bit, and 2.5.75+ (or so, depending on when they release the disk schedulers and the newer kernels) should improve things further. Overall, though, if it's doing a lot of disk stuff expect to wait and wait... You can't do much about this, either, unless you add a second hard drive to the second ultra-bay slot and run a software RAID on it. I am, for what it's worth, considering doing exactly this on my system... > I have never used any other OS on my laptop, other than Debian, so I > don't know how the performance would be, using other distros, or other > OSes. However it seems strange to me, that my laptop system is so > slow. Windows is probably going to feel a bit more snappy, mostly because of the implementation of it's UI code. Other Linux based distributions are going to make very little difference. > I have heard that Debian's default installation, is a safe one, which > doesn't take advantage of many of the system's bells and whistles. I > wonder, are there any things that I can do to somehow tweak my system, > and make it faster? The biggest thing that improves performance for a P4 is getting a recent 2.5 kernel (at your own risk, of course), building that, then rebuilding glibc to take advantage of the recent sysenter support. That's worth around 30% less overhead on any syscall. Other than that, not much is going to
