delphij's Chaos


01 Apr 2004

Alan Cox's recent improvements to FreeBSD VM subsystem

Dr. Alan Cox (alc@) has committed several improvements to FreeBSD’s VM implementation, and this brought significant performance gains on 5-CURRENT.

The most essential commits are here and here. After these changes, there is surprisingly huge performance gains, a benchmark done by Dr. Alan has shown:

“Surprisingly, I saw the greatest gain from this change on such a machine: lmbench’s pipe bandwidth result increased from ~1050MB/s to ~1850MB/s on my 2.4GHz, 400MHz FSB P4 Xeon.”

This quickly inspired Matt Dillon and he has a new proposal of the “XIO” concept. Recently, DragonFly is doing many changes on performance area, and hopefully, with XIO, the clustering performance of DragonFly will be much better.