@brandon220 said in How to take advantage of virtualization. Major products get updated:
I plan on setting this up in the lab soon. dm-cache also sounds interesting. I've never touched software RAID because 95% of my environment has been MS for a long time. Always have gone the hw raid route.
https://www.redhat.com/en/blog/improving-read-performance-dm-cache
Redhat did some testing with an SSD but it looks ugly. 5 passes and no performance improvement using a SSD. I suspect they are hamstrung by the patent minefield that is ARC (IBM of all people has this patent BTW) and the subsidiary cool optimizations that have been made to it (ARC was intended for CPU cache originally, your storage fun fact of the day!). Also I suspect the IO path on this thing isn't the cleanest. Looks like the Linux kernel file cache is going to be faster which if I"m using that I might as well just give memory to the guest and let it sort it out (especially with the lack of dedupe or single instancing of this cache).
If your looking to speed stuff up I say get "the good stuff".
We got some PMEM DIMMS in the lab, and this stuff is face melting fast. You can "bolt" it on with a DAX file system, but the best way to use it is with applications that have been redesigned to support it. We forked REDIS to support this and got latency 12x better than using local NVMe drives, and 2.8x better tha DAX.
Oracle had 57x better operational latency.
0_1534916586664_Redis.PNG
0_1534916590424_Oracle.PNG
