Posted on 23 April 2007 @ 23:15

edited 23:15

Using software RAID5 requires an intelligent 'implementation' to deliver performance. Good softwarematic RAID5 solutions like geom_raid5, will deliver write performance well in excess of 100MB/s.

Unfortunately, onboard RAID5 usually has a weak implementation. This means the write performance will be as low as 10MB/s while requiring lot's of CPU cycles. And since it's all implemented by drivers it's often unsupported on Linux and BSD operating systems.

So my recommendation is to use either Linux or FreeBSD and use pure software RAID instead, requiring no onboard RAID just connect your disks and configure them in a software RAID5 setup once you setup your OS. FreeBSD offers best performance, using geom_raid5. FreeNAS is a small and very userfriendly mini-OS which is dedicated to network storage and also uses geom_raid5 since it's based on FreeBSD. You can use either one of them to achieve good performance.

Make sure you connect your disks to the SATA connectors provided by your chipset, and not some "extra" chip like Promise/JMicron/Silicon Image which often use the slow PCI-bus. The onboard connectors provided by your chipset have no such bus problems and are the fastest to use.

Take control of the input and you shall become master of the output.

Posted on 8 June 2007 @ 20:04

Hi i'm also building a FreeNAS box with geom_raid5. Would an Athlon 64 3200+ be sufficient to achieve gigabit performance (100MB/s) or do i need a dualcore processor? geom_raid5 will be faster than onboard RAID, right?