While unintentional, the results from our first test run across Ubuntu 6.06.1, 8.04.4, and 10.04 were rather dramatic. Between the LTS releases of Ubuntu 6.06.1 and 8.04.4 there is a rather significant improvement in performance (+46%), but those gains are more than wiped out with Ubuntu 10.04. In fact, with this simple static web server benchmark, Ubuntu 6.06 is more than 17x faster than how Ubuntu 10.04 LTS is set to perform. Much of this performance drop is attributed to the use of the EXT4 file-system by default in Ubuntu 10.04. Other benchmarks at Phoronix have shown similar performance drops in Apache when using EXT4. Of course, we are just looking at the performance numbers, but the data stored on the EXT4 file-system should be more reliable and offer other benefits not shown within benchmark results.
Similarly, the PostgreSQL performance has too degraded with time. However, between Ubuntu 6.06 and 8.04 the performance was more than halved when Ubuntu was still living with EXT3.
The LZMA compression results show minor performance improvements made with each succeeding LTS release. Ubuntu 10.04 LTS is looking like it is handling LZMA compression about 11% faster than Ubuntu Dapper Drake and about 4% over Ubuntu Hardy Heron.
Between Ubuntu 6.06.1 LTS and Ubuntu 8.04.4 LTS there is a huge spike in performance for our ThinkPad T60 test system. This is because the 32-bit default kernel in Dapper was not fully SMP supported and thus was just taking advantage of one of the Core Duo's cores. With Ubuntu 8.04 and beyond, the 32-bit version properly handles multiple processing cores. Between Ubuntu 8.04 and 10.04 there is about a 4% improvement in 7-Zip to be found.