SOLVED Can the system disk be used as a write cache?

[qq8554650]

translation from google
The system disk consists of two 800G SSDs (Attach). Can some of them be used for write cache?can be reinstalled

 

[jgreco]

SSDs (Attach). Can some of them be used for write cache?

No. In the ZFS model, only your system's main memory is write cache. SSD is used for read cache. If you are operating under the mistaken assumption that SLOG/ZIL is some sort of write cache, please disabuse yourself of the notion. It is not.

Some insights into SLOG/ZIL with ZFS on FreeNAS

What is the ZIL? POSIX provides a facility for the system or an application to make sure that data requested to be written is actually committed to stable storage: a synchronous write request. Upon completion of a sync write request, the underlying filesystem is supposed to guarantee that a...

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[sretalla]

system disk

I have to waste an entire drive just for booting?

This resource was originally created by user: jgreco on the TrueNAS Community Forums Archive. Please DM this account or comment in this thread to claim it. With the advent of TrueNAS Scale, we seem to be getting a large number of people from the Linux community who are not quite grasping what...

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