Why is the write performance not improved after I configured SSD write cache？

Problem/Symptom

Why is the write performance not improved after I configured SSD write cache？

Solution

SSD caching on ZFS serves as memory extension for the system,
and the write cache will only be used when the memory of system is running out, thus the effect seems not to be obvious.
To verify whether the SSD write cache will take effect, you may consider to disable the cache of NFS on system, please refer to steps below for disabling system cache:

1. Click "Control Panel".
2. Go to "Folder" under "File Sharing".
3. Click "NFS Host" tab.
4. Click "Add" to create or "Edit" to edit NFS host property.
5. Uncheck "Async write" to disable system write cache.

Apply to

All QSAN XCubeNAS models