I am running ActiveMQ on my Macbook Pro that runs Ubuntu 10.10, 32 bits with an ext4 partition.
Linux iker-laptop 2.6.35-23-generic-pae #40-Ubuntu SMP Wed Nov 17 22:32:51 UTC 2010 i686 GNU/Linux
If I enable persistence in ActiveMQ the performance drops terribly. I've tested the same thing on other machines and the difference is of 2 orders of magnitude.
There is a tool with activeMQ to test the HD, here are the results:
iker@iker-laptop:~/apps/apache-activemq-5.4.1$ java -classpath lib/kahadb-5.4.1.jar org.apache.kahadb.util.DiskBenchmark Benchmarking: /home/iker/apps/apache-activemq-5.4.1/disk-benchmark.dat Writes: 146171 writes of size 4096 written in 11.074 seconds. 13199.477 writes/second. 51.560455 megs/second. Sync Writes: 197 writes of size 4096 written in 10.006 seconds. 19.688187 writes/second. 0.07690698 megs/second. Reads: 5589861 reads of size 4096 read in 10.001 seconds. 558930.2 writes/second. 2183.321 megs/second.
Performance for Sync Writes is s**t. There must be something misconfigured, but this is the only app where I've noticed a HD performace issue.
hdparm throws expected values:
iker@iker-laptop:~$ sudo hdparm -tT /dev/sda /dev/sda: Timing cached reads: 6282 MB in 2.00 seconds = 3141.73 MB/sec Timing buffered disk reads: 240 MB in 3.00 seconds = 79.88 MB/sec