Don't want to get my hopes up, but so far it appears to be the write cache that's disabled causing me the majority of my grey hairs.
Enabled write caching in the system BIOS and so far, it appears that the speeds have more than doubled. Problem is it's not battery-backed, so if the server loses power I'm probably going to have data-loss on my hands.
The entire VM instance in this case though is to serve only as a destination for Veeam replicates, so don't think I need to be too bothered in that regard. I'm yet to test this again in the wild, so to speak, but from the limited testing I've done so far (upload a large file to a datastore via the datastore browser with and without write caching) seems promising.
Interestingly, running esxtop and checking the disk stats reported more than 20MB/s, but timing the upload manually and calculating the speeds revealed the real-world rate to be closer to 10MB/s...
Still, it's far quicker than it was without write caching.
Not sure if the kit is really up to the task either. The drives are WD Caviar Greens, doesn't look like the world at large has historically been too impressed with its performance.
Anyways, I reckon it's about time to test this in the field and see how it goes. Will update once I've had more concrete proof.
