The list below shows the active filesystems. The /backups_ filesystems are a mirrored copy of the primary filesystems to be used in case one of the RAID arrays is unavailable, allowing the system to be booted for recovery purposes.
The actual filesystems provided to the network are two 2TB filesystems, named /data0 and /data1. Additionally, two 120GB filesystems named /work0 and /work1 are provided for scratch space for network users.
Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/da0s1a 507630 51894 415126 11% / devfs 1 1 0 100% /dev /dev/da0s1d 16244334 37408 14907380 0% /var /dev/da0s1e 16244334 6 14944782 0% /var/crash /dev/da0s1f 16244334 1607096 13337692 11% /usr /dev/da0s1g 8122126 62 7472294 0% /tmp /dev/da0s1h 8121252 26 7471526 0% /sysprog /dev/da0s2h 120462010 4 110825046 0% /work0 /dev/da0s3h 2079915614 859342082 1054180284 45% /data0 /dev/da1s1a 507630 249998 217022 54% /backups_root /dev/da1s1d 16244334 38762 14906026 0% /backups_var /dev/da1s1e 16244334 62 14944726 0% /backups_var_crash /dev/da1s1f 16244334 1686090 13258698 11% /backups_usr /dev/da1s1g 8122126 126 7472230 0% /backups_tmp /dev/da1s1h 8121252 86 7471466 0% /backups_sysprog /dev/da1s2h 120462010 4 110825046 0% /work1 /dev/da1s3h 2079915614 1474939512 438582854 77% /data1
Figure 7: A screenshot showing the filesystem's capacity
Figure 7 is a Windows view of one of the server's filesystems, showing its 1.93TB total capacity. Please note that this system is firewalled from the Internet, so don't bother trying to come visit. It will only bother me and cause me to make unhappy noises at your ISP.
As a basis of comparison to other NAS tests on SmallNetBuilder, I ran iozone on RAIDzilla using a Dell Dimension 8400 w/ 3.6GHz CPU, 2GB RAM running Windows XP Home. The network adapter was an Intel MT1000 connected at 1000Mbps, full duplex w/ 9K jumbo frames enabled. Figures 8-11 were taken using the NAS Performance Charts.
Figure 8: Write performance comparison, small file sizes
Figures 8 and 9 show that RAIDzilla tops the charts for 1000 Mbps RAID 5 write performance for file sizes 16 MB and under, but comes in second to the Linksys NSS4000/4100 [reviewed here] for read. Note that the NSS4000 used only 4K jumbo frames while the RAIDzilla used 9K.
Figure 9: Read performance comparison, small file sizes
Figures 10 and 11 show a reversed trend for file sizes 32 MB to 1 GB. The Linksys does slightly better than RAIDzilla for write, but RAIDzilla crushes the Linksys for reads.
Figure 10: Write performance comparison, large file sizes
Figure 11: Read performance comparison, large file sizes
I also did some performance testing between a pair of RAIDzillas using FTP (get /dev/zero /dev/null) and was able to achieve > 650Mbit/sec. Performance of actual file serving is limited by the speed of the disk subsystem, of course.
I haven't done a lot of performance tuning yet, mostly because this level of throughput is more than adequate for my applications.
It may not be the easiest way to go. But by designing and constructing your own NAS, you get a system with all the features you want...and know how to fix it when it breaks!
This article originally appeared as The RAIDzilla Project.