[Important Security Notice] Fake Qfinder Pro Websites Detected. Learn more >

What are the different storage settings for shared folders and LUNs?

Last modified date: 2025-07-04

Applicable Products

QuTS hero h5.3.0 or later
Storage Manager
iSCSI & Fibre Channel

Details

When creating or editing a shared folder or LUN, you can configure certain storage settings to optimize user experience and performance:

Setting	Description
Compression	QuTS hero compresses the data in the shared folder or LUN to reduce the size of stored data. Enabling compression also reduces the total number of blocks that QuTS hero needs to read and write, increasing read and write speeds for the shared folder or LUN. Note Compression does not impact overall system read/write and processor performance on ZFS file systems. Compression is enabled by default. We do not recommend disabling this setting unless necessary.
Deduplication	QuTS hero reduces the amount of storage needed by eliminating duplicate copies of repeated data. Important To enable deduplication, your NAS must have at least 16 GB of memory.
SSD read cache	QuTS hero adds data from this shared folder or LUN to the SSD cache to improve read performance. Note To enable this setting, you must first create the SSD cache. For details, see Creating the SSD cache. The SSD cache is not available to a shared folder or LUN in the following situations: The shared folder or LUN's parent storage pool contains only SSDs. The shared folder or LUN's parent storage pool does not contain any SSDs.
Fast clone	Fast clone enables QuTS hero to create copies of files faster. It also saves storage space by modifying file metadata, allowing original and copied files to share the same data blocks. Note This setting is only available for thin shared folders and thin LUNs. Fast clone only works when the copied file is created in the same shared folder or LUN containing the original file. Fast clone does not improve the speed of snapshot restoration operations such as restoring files from a snapshot, snapshot revert, or snapshot clone.
ZIL Synchronous I/O mode	The ZFS intent log (ZIL) synchronous I/O mode determines whether to prioritize data consistency or performance when reading and writing data in the shared folder or LUN. There are three options to choose from: Auto: QuTS hero uses synchronous I/O or asynchronous I/O based on the application and the type of I/O request. Always: All I/O transactions are treated as synchronous and are always written and flushed to a non-volatile storage (such as an SSD or HDD). This option gives the best data consistency but might have a small impact on performance. None: All I/O transactions are treated as asynchronous. This option provides the highest performance but has a higher risk of data loss in the event of a power outage. If you select this option, ensure that a UPS (uninterruptible power supply) is installed.
Performance profile (block size)	This setting allows you to specify the size of data blocks in the shared folder or LUN. Different options are suitable for different applications. Note This setting can only be configured during shared folder or LUN creation. After creation, this setting is fixed and cannot be changed. The default value for shared folders is 128K. The default value for LUNs is 64K.
Alert threshold	When the used capacity of the shared folder or LUN exceeds the specified threshold, the system sends an alert notification.

Further Reading

QuTS hero User Guide

Was this article helpful?

Yes. No.

100% of people think it helps.

Please tell us how this article can be improved:

The article is missing important information
The article's solutions do not work
The article is too complicated
The article contains incorrect information
The article is out-of-date

If you want to provide additional feedback, please include it below.

If you want to provide additional feedback, please include it below.