Performance - Infrant Technologies Readynas User Manual

Performance

If you wish to tweak the system performance, select the Performance tab in the System menu.
Note that some of the settings suggest that you utilize an Uninterruptible Power Supply (UPS)
before enabling that option.
Select Enable disk write cache if you want to utilize the performance advantages of write caching
on the hard disks. For the utmost protection of data, you should utilize a UPS to back up the
ReadyNAS because there is a slight chance that data queued up in the cache will be lost should a
power failure occur while the system is writing data to the disk.
The Disable full data journaling is also recommended only if the NAS has UPS protection.
Without battery backup, there is a small chance that parity written to a disk in a RAID set may
become out of sync with the data disks if a power failure suddenly occurs, possibly causing incorrect
data to be recovered if one disk fails. Without full data journaling, disk write performance will
increase substantially.
Select Disable journaling altogether if you understand the consequences of the 2
and you also don't mind a long file system check (only after unexpected power failures). File system
journaling allows disk checks of only a few seconds verses possibly an hour or longer without
journaling. Disabling journaling will improve disk write performance slightly.
Note
You can buy a UPS with USB monitoring for less than $50 (US dollars). By
safely allowing the performance options to be checked, you can effectively
double your write performance and provide uninterrupted service of your
ReadyNAS for a very low price.
Page 61
61
nd
option above,