FC6 on AMD Dual Core

[Phil Meyer]

Srikanth Konjarla wrote:
> Yes. I see degraded performance on the laptop and i totally understand
> that would cause latency in any heavily disk bound applications.
> However, i am not sure how it will affect the loading of application(s)
> and desktop navigation in general.
>
> Srikanth
>
> Oliver Schulze L. wrote:
>   
>> Maybe the problem is the hard disk performance, do a quick check with:
>> hdparm -t /dev/sda
>>
>> twice(because of caching) in each PC anc compare
>>
>> HTH
>> Oliver
>>
>>     
>
>   

Several things to consider in basic architectural differences.

1.   Your AMD laptop has a slower disk drive.
2.   Your AMD laptop probably has slower memory timings.
3.   Your AMD laptop may have less memory.
4.   Your Laptop probably has a slower video card in it.


There are other issues as well, but lets just examine the impact of 
these things in general desktop usage.

Slower disk:

This will impact application startup because reads are slower.
To demonstrate this effect, time the startup of Firefox just after a 
reboot.  Then close Firefox and time the startup of Firefox again.  Do 
it a third time just for grins.  You will see a marked decrease in the 
startup time of Firefox the second and third time compared to the 
first.  Why?  File caching by the operating system.  The first was from 
disk, the second and third are from cache.  repeat the timings on the 
desktop, and pay particular attention to the first timings as related to 
disk timings, and the second and third timings in relation to memory 
performance.

Slow disk reads will also impact any application that forces paging 
activity.

Slower memory timings:

Memory timing is critical for application performance, but most desktop 
applications sit and wait for user interaction.  Memory timings will 
impact application load times, compiler times, gaming performance, and 
many other specialized applications.  A 3D desktop like Beryl will 
'feel' faster on a system with great memory timings and a great video card.

The amount of memory installed can also make a difference.  All modern 
UNIX/Linux kernels will use all available memory.  The bulk of memory 
not tied to applications is used for caches of various sorts.  As 
demonstrated with the Firefox startup times, disk cache does impact 
desktop performance.  Other types of caching also impact general 
performance.  UNIX/Linux loves memory.  The more the better.  In 
general, you will see a performance difference on an otherwise identical 
system between 512MB RAM and 2GB RAM installed.  This assumes an active 
desktop user, of course.

Video Card Differences:

This can be the most critical difference in desktop performance, even in 
2D, which most desktops are rendered.
Driver differences are always suspect.
Fonts and display resolutions can impact performance, and plain old 
'look bad'.
Using a font server is mpre efficient than reading fonts from disk each 
time.
Using fonts 'as is' instead of 'rendering' fonts takes mush less CPU.
Is the laptop display resolution set to recommended (actual) ?
All of these things can tax a video card even in 2D.

Generally speaking, a laptop will underperform a desktop of the same 
relative components, by design.  A laptop uses major components designed 
for lowe power and low heat.  This translates to 'slower' than desktop 
components.

Typical 'slower' components include:
Memory
Disk
Video

For instance:

A mobile GForce 7950 GTX is NOT equivalent to a desktop version of the 
same card.

Good Luck!