Summary of Comparisons

Linux Software RAID Performance Comparisons

This page summarizes the default decisions made based on previous summaries.

The Controller

Motherboard: Asus K8N-DRE
Processors: Two 1.8GHz Opteron 244 OR two 2.4GHz Opteron 250
RAM: 8GB DDR400 running at 333MHz
OR 4GB DDR400 running at 400MHz
Slots: 1 32-bit PCI; 1 PCI Express x16
Drives: Seagate Barracuda 7200.11 1000Gbytes ST31000333AS
Drive cage: Supermicro CSE-M35T-1B 5-Bay Enclosure (fits in three 5-inch chassis bays; sells for about $100-$120 from newegg.com)

Read Percentage: 100% (pure read), 50% (mixed), 0% (pure write)
Random Percentage: 0% (sequential), 100% (random)
Thread counts: 1 and 20
Block sizes: 4k, 8k, 32k, 64k, 256k, 1m, 4m, 8m, 64m
Targets: All 5 driver were tested simultaneously, as well as each drive individually.
All I/Os are issued using the O_DIRECT flag.
All tests last 30 seconds.
To invalidate both the server and the client cache, between each test the remote NFS mount was unmounted on the client, the NFS server was stopped on the server, and the local file system was unmounted on the server. Without these steps, we would have only been measuring cache effects.
The server mounted the encrypted file system with noatime,nodiratime, the server started nfs-kernel-server without any special configuration, and the client mounted the exported file system with noatime and with rsize and wsize set to the specified values.