Write-back disk optimization
Follow the steps below to optimize your writeback disk:
- Enable the client cache.
- When you have more than 20/30 computers then one write-back disk is not enough. We recommend using two or more write-back disks.
- If you have multiple disk for writeback disks then check if they are set properly in the Disk tab in Boot page. If they are not set then set it. Refer to Disk configure.
- If you have 2 writeback disks and your clients are still lagging then increase your writeback disk cache. (1024 – 3072 MB is recommended cache per Writeback disk).
- We recommend using SSD for writeback disk, as it has higher read/write speed and can handle large numbers of read/writes compared to traditional HDD.
- If you already have an SSD on each PC then you can use it as a local writeback disk so that it will improve performance.
- When you choose a disc for writeback look at IOPS for random write, it should be at least 80K-90K.
For example: We recommend the SSD Samsung EVO 850 (or EVO 860) for writeback because it has IOPS up to 90K for random write.
IOPS for random write is one of the main performance indicators of SSD for diskless systems, since one disk is simultaneously used by several clients and they write (and read) data from different parts of the disk at the same time. i.e. the more operations per second can make the SDD the higher the data rate.
- Check whether there is any program which is doing a lot of read/write on the disk. If there is, you need to find it and stop its service.
- If you are using Windows 7, check whether it is installed with the latest patches. If not, please install the latest patches in your Windows 7.
- Your clients may have idle time disk defragmentation scheduled and running when pc becomes idle.
To fix this, you need to delete the scheduled task in client PC in super client mode.
a. Run Command Prompt as administrator
b. Run the command :- schtasks /Delete /TN "\Microsoft\Windows\Defrag\ScheduledDefrag" /F
This will delete the defragmentation schedule and help elevate the writeback idle issue.