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BP1024 Scaling and Best Practices for Virtual Workload Environments with the FS7500 16
Figure 9 Write throughput with different load balancing techniques
Since port-based and MAC-based load balancing maps traffic to a single NIC uplink, the measured
throughput was close to the line rate of one NIC. With IP hash-based load balancing and using
multiple target IP addresses, the NFS traffic was load balanced across all four NIC uplinks and we
obtained throughput close to line rate of all four NICs.
3.4 NAS File Systems and ESX datastores
In addition to the networking and host configuration listed in section 3.1, a system administrator has to
make various choices like the number of NAS volumes and ESX datastores to be configured and the
number of host side NICs used to communicate with NAS. The following subsections discuss the
impacts of some of these variables.
3.4.1 Number of datastores
Increasing the number of NAS file systems (NAS virtual containers) on the FS7500 does not
significantly affect the network throughput performance (read and write throughput in MBps). A NAS
file system is a virtual entity and does not affect performance throughput. Performance is primarily
affected by the number of FS7500 appliances and the NAS reserve disk configuration. NAS file systems
virtually span the available NAS reserve space, which can be increased or decreased based on dynamic
needs. Similarly, additional FS7500 appliances can be added to an existing appliance and all NAS file
systems would be automatically load-balanced across the available appliances. Administrators can
choose to deploy multiple NAS file systems for ease of management (file quotas) and segregating data
protection tasks such as snapshot or backup for classes of data. These NAS file systems are mounted
as datastores on the ESX host via NFS exports. In this test we varied the number of NAS file systems
and kept the number of NAS service virtual IP addresses and number of host NICs to access the
datastores constant.
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Port based load balancing MAC based load balancing IP Hash based load balancing
Write throughput (MBps)
Maximum available
bandwidth from one ESX
host (4 x 1GbE) utilized