White Papers

Dell HPC NFS Storage Solution High Availability Configurations with Large Capacities
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InfiniBand random write performance Figure 13.
The NSS-HA write performance is limited by several design factors including write cache mirroring on
the RAID controllers, XFS wsync mount option and NFS sync export option.
The read performance is not impacted by these choices, additionally, read operations have a lower
overheard than write operations in RAID 6. For these reasons read performance is much better than
writes. Results of the random read tests are shown in Figure 14. From the figure, random read IOPs
scale to ~10000 IOPS for the 288 TB configuration and to ~4500 IOPS for the 144 TB configuration. Both
random writes and reads are impacted by disk seek latency and the additional disk spindles in the 288
TB solution help the larger capacity configuration perform better. Actual workloads could see better
read IOPS than presented here for situations where cache on the client and NFS server can be
exploited. As part of this study (but not shown here), read performance of the order of ~50000 IOPS
was measured for the cases where cache helped performance
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IOPS
Number of concurrent clients
IB Random Write Performance
144 TB -- NFSv3 288 TB -- NFSv3