2.4 vs 2.6 Linux Kernel Shootout

FyRE666 writes "Infoworld are currently running an interesting comparison of the 2.4 series kernel against the new 2.6 release on Xeon, Opteron and Itanium CPUs with some surprising benchmark results for common server-related tasks. Basically the new scheduler helps the 2.6 kernel to cream the old 2.4: Samba tests showing up to 73% speed increases, MySQL showing up to 29% and Apache serving dynamic content up to 47% faster!"

Comments

Error

[popa]

tried to get this in before you posted it... but dynamic only went up 22% for apache.... static went up 47%

Re:Impressive

[JebusIsLord]

well i know the preemtive and low-latency changes (while available as patches to 2.4) are included in 2.6, and make a significant difference to GUI responsiveness.

Re:NTFS Read/write support?

[jensend]

The native ntfs driver supports writing only if the write operation wouldn't disturb any of the metadata- that is, you can't create or delete any files but you can safely overwrite a file if you don't change its size. This is more useful than it sounds at first- you can use a loopback file on the ntfs partition for anything you want.

Re:My thoughts...

[owlstead]

No, you aren't missing something. Applications will still run as they did, except when they are heavily multithreaded. Starting up something CPU-cycle expensive and typing in open office might give you an idea.

But all in all, it's the kernel. End users should be nicely unaware of it. Don't expect any fireworks to go off, most of the time you notice a kernel you will have hoped you didn't :).

Re:Linux in cache?

[runderwo]

Caching is controlled completely by the CPU, transparent of the programmer.

Only in some designs. Architectures like MIPS allow for both a cache-coherent or non-cache-coherent design. In a non-cache-coherent design, the cache is not transparent, and the kernel programmer is responsible for cache management; marking pages as dirty, flushing cache, etc. These designs are significantly more difficult to program and are present on some SGI machines, making porting to those machines a significant task.

Theoretically, higher performance can be achieved in a non-cache-coherent design, since the programmer would ostensibly know more about which data is most frequently used on his system and be able to customize his kernel for that. Also, it requires less glue logic on the board. However, the intent may be thwarted if the programmer doesn't have all the documentation (or skills) necessary to make efficient use of a software controlled cache.