Very old but still as relevant… and very interesting too! Directly go to “anti-tip” section of this article.
“The moral of the story is: don’t get tricky. C programmers often try to minimize the number of lines of C in their program without consideration for what the compiler will generate. When in doubt, write clear code and give the optimizer a chance to maximize performance. Look at the compiler output. Your code will be easier to debug and probably faster too.”
One of my Fedora 10 systems used to freeze very frequently. After lot of looking around I found its because of “KWin Composing” which gives OpenGL driven special effects for desktop. Unfortunately, Linux has always been bad at radeon drivers, so it better to disable these effects especially if you have radeon video cards.
in ~/.kde/share/config/kwinrc:
in [Compositing] section change Enabled=true to Enabled=false.
Reboot after this change. Now I never get any system freeze - as is expected from solid Linux system :)
Here is link to paper (pdf) (MP3)
Recently I came across this paper published in OSDI ‘08. Its an extension to VMware’s page-sharing and shows some amazing and hard to believe results. VMware page-sharing mechanism scans memory for all VMs and maps pages with same contents to a single page. This achieves memory savings if multiple VMs are hosted running same OS. However, with technique discussed in this paper, we find pages that are nearly same. For such pages, they save a base page and other similar pages as delta of original page. For pages which are not similar to any other page are simply compressed. Their benchmarks shows upto 45% more memory saving over ESX page-sharing under some (specially crafted) workload.
[Read More]