Phil Meyer wrote: > 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. > Thanks for the detailed response. I guess the laptop is suffering from slower disk. I have posted my SATA disk related question sometime back and it appears that only my laptop disk (Samsung HM100JI) is showing slower performance with sata_nv. Perhaps, i have to change the disk and try. Srikanth > 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! > >
