Home > Workload Solutions > SQL Server > Best Practices > AMD-Based SQL Server Best Practices on Dell PowerEdge R740 and PowerMax 2000 > Storage Best Practices > Day One Best Practices > PowerMax: Storage Directors Ports and Interface Emulations
The two validation tests for the PowerMax Storage Directors were combined into one best practice. The first test involved configuring the PowerMax Director to use only those interfaces used by the business. The second test involved increasing the number of front-end connections to improve bandwidth between the PowerMax storage and PowerEdge servers. These best practices were combined as they both apply to configuring the PowerMax Directors.
Category | PowerMax Storage |
Product | PowerMax front-end connections |
Type of best practice | Performance Optimization |
Day and value | Day 1, Highly recommended |
Overview of Optimizing Director Interfaces
PowerMax storage arrays use bricks that enable customers to add power, performance, and capacity to an existing array. Each PowerMax brick has two engine directors. These directors support multiple functions including front-end I/O modules. The front-end I/O modules provide connectivity to the array using various interfaces including Fibre Channel SCSI, Fibre Channel NVMe, iSCSI, and others. In the best practice validation tests, we used only the Fibre Channel interface, thus providing the ability to disable unused interfaces such as Fibre Channel NVMe and iSCSI.
Unused interfaces on the directors consume processor resources even if running in an idle state. By disabling interfaces, the business can direct more processing power to the interfaces that are heavily used. The goal is to optimize the director interfaces to support only those used by the business, thus optimizing performance.
The origin of this best practice is from Dell EMC support. We highly recommend working with support to validate whether this director interface optimization will work for your business.
Overview of Adding Director Front-end I/O Modules
There are four front-end I/O modules per director. In the baseline configuration, we used one of the total four front-end I/O modules/director. The following table shows; each port 1 of the four directors was used. The two other front-end modules on director 4 were reserved for replication. Each front-end module was a 32 Gbps Fibre Channel connection and the baseline connection consisted of six modules.
Table 1: Directors and front-end I/O modules used
Director number | Port number | Connected | HBA number and port |
1 | 1 | Connected | HBA 1, Port 1 |
2 |
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3 |
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4 |
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2 | 1 | Connected | HBA 1, Port 2 |
2 |
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3 |
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4 |
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3 | 1 | Connected | HBA 2, Port 3 |
2 |
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3 |
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4 |
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4 | 1 | Connected | HBA 2, Port41 |
2 |
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3 | Reserved for replication |
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4 | Reserved for replication |
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For this best practice, we added one front end I/O port (2) on each director for a total of eight connections to the server. The following table shows the ports that were added (marked in light gray):
Table 2: Directors and ports added
Director number | Port number | Connected | HBA number and port |
1 | 1 | Connected | HBA 1, Port 1 |
2 | Connected | HBA 2, Port 3 | |
3 |
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4 |
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| |
2 | 1 | Connected | HBA 1, Port 2 |
2 | Connected | HBA 2, Port 4 | |
3 |
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4 |
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3 | 1 | Connected | HBA 1, Port 1 |
2 | Connected | HBA 2, Port 3 | |
3 |
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| |
4 |
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4 | 1 | Connected | HBA 1, Port 2 |
2 | Connected | HBA 2, Port 4 | |
3 | Reserved for replication |
| |
4 | Reserved for replication |
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The additional front-end ports used in this best practice showed the greatest improvement of all the storage recommendations. Doubling the connections to the database server provided substantial improvements.
Recommendation
The combination of the PowerMax Directors in two tests, removing unused interfaces, and connecting additional front-end I/O modules provided a substantial performance boost. Performance improvements were shown in the following metrics:
Both TPC-C metrics (NOPM and TPM) showed a substantial improvement: the number of orders completed and transactions processed increased significantly. Correspondingly, array IOPS also increased significantly. The PowerMax average read and write times dropped significantly, indicating faster responses from storage.
Server CPU utilization increased, which is a positive indication of more efficient use of the cores in the server. Until this best practice was implemented, processors were likely waiting on read and write I/Os from the storage array. Now that the average read and write response times are faster, the processors are processing more data and so are being more efficiently used.
Overall, the best practice of adding PowerMax directors and front-end I/O modules and disabling unused interfaces in the director can significantly improve performance. We recommend implementing this best practice as a Day 1 activity, as it is a highly recommended configuration that optimizes database performance.
Implementation Steps
Additional Resources
This best practice was referenced from the Deployment Best Practices for SQL Server Database with Dell EMC PowerMax.