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QNAP

QuTS hero 5.0.x

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Storage Global Settings

Setting

Description

Pool Scrubbing Schedule

Pool scrubbing detects and automatically repairs damaged data blocks in the ZFS file system.

Important:

The scrubbing task may reduce the storage pool read and write performance. You should schedule pool scrubbing to run during times of low NAS usage. You can also click Exclude Times to specify times and days of the week during which scrubbing will not run.

Clean Deduplication Table

When ZFS performs deduplication, it records duplicate data in a deduplication table. Cleaning removes unused entries from the deduplication table.

Important:

The clean deduplication table task may reduce the system read and write performance. You should schedule this task to run during times of low NAS usage.

ARC RAM Usage

ZFS uses Adaptive Replacement Cache (ARC), an algorithm which uses as much RAM as possible to optimize system performance. Lowering the maximum ARC RAM usage can provide applications with more access to RAM, but may affect ZFS performance.

Warning:

Increasing the maximum ARC RAM usage can cause currently running applications to close. Review your NAS RAM usage before you proceed.

Note:

This setting is disabled if the total NAS RAM size is 8 GB, in which case the minimum and maximum ARC RAM usage must be the same.