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QTS 5.0.x

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iSCSI Performance Optimization

You can optimize the performance of iSCSI by following one or more of these guidelines:

  • Use thick provisioning (instant allocation). Thick provisioning gives slightly better read and write performance than thin provisioning.

  • Create multiple LUNs, one for each processor thread on the NAS. For example, if the NAS has four processor threads, then you should create four or more LUNs.


    Go to Control Panel > System > System Status > System Information > CPU to view the number of processor threads.

  • Use separate LUNs for different applications. For example, when creating two virtual machines which intensively read and write data, you should create one LUN for each VM to distribute the load.

  • You can use iSER (iSCSI Extensions for RDMA) for faster data transfers between QNAP NAS devices and VMware ESXi servers. Enabling iSER requires a compatible network card and switch. For a list of compatible network devices, see https://www.qnap.com/solution/iser.