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Load Balancing

Load Balance Policy

Multi-path drivers select the I/O path to a virtual disk through a specific RAID controller module. When the multi-path driver receives a new I/O to process, the driver tries to find a path to the current RAID controller module that owns the virtual disk. If the path to the current RAID controller module that owns the virtual disk cannot be found, the multi-path driver migrates the virtual disk ownership to the secondary RAID controller module. When multiple paths to the RAID controller module that owns the virtual disk exist, you can choose a load balance policy to determine which path is used to process I/O. Multiple options for setting the load balance policies let you optimize I/O performance when mixed host interfaces are configured.

NOTE: For more information on Load Balance Policy, see your operating system’s manual and updates.

You can choose one of the following load balance policies to optimize I/O performance:

•Round robin

•Least queue depth

•Least path weight (Microsoft Windows operating systems only)

Round Robin With Subset

The round robin with subset I/O load balance policy routes I/O requests, in rotation, to each available data path to the RAID controller module that owns the virtual disks. This policy treats all paths to the RAID controller module that owns the virtual disk equally for I/O activity. Paths to the secondary RAID controller module are ignored until ownership changes. The basic assumption for the round-robin policy is that the data paths are equal. With mixed host support, the data paths might have different bandwidths or different data transfer speeds.

Least Queue Depth

The least queue depth policy is also known as the least I/Os or least requests policy. This policy routes the next I/O request to a data path that has the least outstanding I/O requests queued. For this policy, an I/O request is simply a command in the queue. The type of command or the number of blocks that are associated with the command are not considered.

The least queue depth policy treats large block requests and small block requests equally. The data path selected is one of the paths in the path group of the RAID controller module that owns the virtual disk.

Least Path Weight

The least path weight policy assigns a weight factor to each data path to a virtual disk. An I/O request is routed to the path with the lowest weight value to the RAID controller module that owns the virtual disk.

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Dell MD3820f, MD3800f Load Balancing, Load Balance Policy, Round Robin With Subset, Least Queue Depth, Least Path Weight
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MD3800f, MD3820f specifications

The Dell MD3800f and MD3820f storage arrays are advanced storage solutions designed to meet the demanding needs of mid-sized businesses and enterprise environments. Both models offer high performance, scalability, and a reliable foundation for data storage that can support various applications.

One of the standout features of the MD3800f and MD3820f is their impressive scalability. The MD3800f can support up to 240 drives, allowing for extensive storage capacity that can be adjusted as business needs grow. Meanwhile, the MD3820f supports up to 192 drives, offering streamlined management without sacrificing performance. This flexible architecture enables organizations to start small and expand their storage configurations as their data evolves.

Performance is another key characteristic of these two storage systems. Equipped with dual active controllers, the MD3800f and MD3820f can provide increased throughput and load balancing, ensuring that applications run smoothly even under high-demand circumstances. With support for both SSDs and HDDs, these storage arrays can achieve a mix of high-speed access and cost-effective capacity. The MD3800f, in particular, offers intelligent tiering capabilities that automatically moves data between different types of drives based on usage patterns, further optimizing performance.

Both models also include advanced RAID configurations, which enhance data protection and availability. Users can select from several RAID levels, including RAID 0, 1, 5, 6, and 10, catering to specific performance and redundancy needs. Additionally, the MD3800f and MD3820f incorporate features like snapshot technology, which allows for point-in-time copies of data for backup or recovery purposes without impacting performance.

In terms of connectivity, the Dell MD3800f and MD3820f offer various interface options including iSCSI and Fibre Channel, enabling seamless integration into diverse IT environments. Management of the arrays is made easy through the Dell Storage Manager, which provides a comprehensive view of storage performance, utilization, and health, making it easier for IT administrators to oversee their infrastructure.

In summary, the Dell MD3800f and MD3820f storage arrays are robust solutions that deliver exceptional scalability and performance. With their advanced features, intelligent data management, and flexible connectivity options, they are well-suited for organizations looking to optimize their data storage capabilities while maintaining high availability and efficiency.
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