VVR 6.1 introduces two new performance features:
- Storage Replicator Log (SRL) Batching to improve application throughput
- Bulk Transfer to improve replication throughput
Note: Both of these features are enabled by default in standalone VVR.
SRL Batching combines multi-threaded application writes to the same replicated data set as a single write to the SRL. Batching reduces the number of IOPS to the SRL thereby resulting in faster write access times and improves application performance. Moreover, this also translates into lower CPU utilization by VVR. In order to be effective, the batching algorithm accumulates multiple parallel SRL IOs before they are written to SRL in a batch.
Bulk Transfer replicates multiple I/Os in 256KB chunks when memory buffers are flushed to the SRL, increasing replication throughput and reducing CPU utilization on the primary server. Bulk Transfer also reduces CPU utilization required to support network data compression.
In lab tests simulating real-world workloads, SRL Batching and Bulk Transfer improved application throughput by as much as 60% and network utilization by as much as 50% respectively.