Dell Unity: How To Balance Load On A Dell Unity Array (User Correctable)

Summary: This article provides guidance on balancing Block and File workloads on a Dell Unity storage system.

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Instructions

The Dell Unity storage system does not automatically balance throughput (I/Os) or bandwidth (MB/s) between Storage Processors (SPs). Manual intervention is required to distribute workloads and optimize performance. 

 

Optimizing Block Workload Performance on Dell Unity

To ensure optimal performance and balance on your Dell Unity storage system, follow these steps:

  1. Monitor System Performance: Use Unisphere's System Performance page to monitor CPU utilization on both Storage Processors (SPs).
  2. Identify Busy LUNs: Determine which LUNs are generating high IOPS or bandwidth, or are located on a busy SP.
  3. Balance LUN Ownership: Manually move busy LUNs from the heavily used SP to its peer SP to balance the load. Refer to our support article for instructions on changing SP ownership.
  4. Distribute Flash Drives: Spread flash drives across all available SAS buses for balanced backend access and increased bandwidth.
  5. Configure Front-End Ports: Ensure sufficient frontend ports (FC/iSCSI) are connected to both SPs to improve load distribution and performance.

Preventive Measures

  1. Apply Host I/O Limits: Set host I/O limits for workloads that tend to consume excessive resources or cause high latency for other applications.
  2. Understand Workload Attributes: Understanding workload attributes, including I/O size and access patterns, is crucial as they can substantially influence the performance of your Dell Unity storage system.
 

Optimizing File Workload Performance on Dell Unity

To balance a file workload on a Dell Unity array, follow these best practices:

  1. Monitor NAS Server Performance: Use Unisphere to monitor NAS server performance, including CPU utilization, throughput, and latency.
  2. Identify Busy File Systems: Identify file systems that are generating high throughput or are experiencing high latency.
  3. Balance File System Ownership: Manually move busy file systems from one Storage Processor (SP) to the other to balance the load.
  4. Distribute File Systems Across Multiple NAS Servers: Spread file systems across multiple NAS servers to improve load distribution and performance.
  5. Configure Front-End Network Ports: Ensure that sufficient front-end network ports are connected to both SPs to improve load distribution and performance.
  6. Optimize File System Configuration: Optimize file system configuration, including block size, striping, and caching, to improve performance.
  7. Apply Quotas and Limits: Apply quotas and limits to file systems and users to prevent any single user or file system from consuming excessive resources.

 

By following these steps and taking proactive measures, balanced and efficient block workload performance can be achieved on the Dell Unity storage system.

Additional Information


Affected Products

Dell EMC Unity, Dell Unity 300, Dell EMC Unity 300F, Dell EMC Unity 350F, Dell EMC Unity 400, Dell EMC Unity 400F, Dell EMC Unity 450F, Dell EMC Unity 500, Dell EMC Unity 500F, Dell EMC Unity 550F, Dell EMC Unity Family

Products

Dell EMC Unity XT 380, Dell EMC Unity XT 380F, Dell EMC Unity XT 480, Dell EMC Unity XT 480F, Dell EMC Unity 600, Dell EMC Unity 600F, Dell EMC Unity 650F, Dell EMC Unity XT 680, Dell EMC Unity XT 680F, Dell EMC Unity XT 880, Dell EMC Unity XT 880F , Dell EMC Unity Family |Dell EMC Unity All Flash, Dell EMC Unity Hybrid, Dell EMC UnityVSA Professional Edition/Unity Cloud Edition ...
Article Properties
Article Number: 000185172
Article Type: How To
Last Modified: 02 Oct 2025
Version:  3
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