Forum Discussion
Storage Replica Async Performance
Should Storage Replica in async replication mode impact write performance? All of my testing has shown that it does (I am using dedicated data and log NVMe drives). In sync mode write performance is...
Yes, data writes still have to go through the local log. If the local
log volume is slow, or at least, same/slower than data volume, perf will
suffer even without the secondary server trip and network. We are
working on a much improved log with much better perf to minimize this;
coming in a later release after RS3 - it is our top priority.
I'm testing SR Async on Windows Server 2019 1809 and there is still a significant write penalty when Storage Replica is enabled. I'm using a pair of NVMe drives (simple volume) for my log that can sustain >3.5GB/s 4K write performance. My data volume gets ~1.6GB/s 4K sequential writes and 174MB/s random before SR is enabled, but only 700MB/s seq and 29MB/s random writes after SR is enabled.
Are there any details on how SR log performance was improved vs. Server 2016?