> Why would you expect Optane Redis to be faster than normal Redis ?
Sorry for the confusion. To clarify, my sentences were separate; I wasn't saying I expected 2x for Redis specifically. I was just saying I didn't expect a 10% slowdown for Redis, and that I expected a 2x improvement typically (not necessarily for Redis).
> And EXISTS/LIST operations are more than just "occasional" operations for data storage systems.
Again, communication issue. I wrote "occasional" in the sense of "a small set of operations", not "infrequent operations". As in, you're going through a list of all operations a DB supports, and occasionally one pops out as potentially substantially benefiting from Optane.
Regardless, your argument misses the point I'm making. The point was: how much of the total workload time do they take up. Even if Optane brought down EXISTS/LIST latency to zero, your workload (including all OS/network/client/etc. overhead) would literally have to be 90% composed of (i.e. overwhelmingly dominated by) EXISTS/LIST checks to get an order of magnitude speed improvement for the user.
Pretty sure you misunderstood. If you forced redis use an SSD (persistent storage) for everything redis normally uses DRAM for and only observed a 10% slowdown, it would be a goddamn miracle!
> how much of the total workload time do they take up
If you're talking about a read-heavy workload, the only good thing about Optane is that it's a little cheaper than DRAM. But those workloads are easy to scale (just buy 2x caches to get 2x throughout) so they're often not worth discussing.
Also reposting my comment from above:
> PCIe Optane was a thing and it achieved 10us latency whereas today's fastest SSDs get 40us. IIRC the DIMM version of Optane was <1us, literally an order of magnitude faster!
Sorry for the confusion. To clarify, my sentences were separate; I wasn't saying I expected 2x for Redis specifically. I was just saying I didn't expect a 10% slowdown for Redis, and that I expected a 2x improvement typically (not necessarily for Redis).
> And EXISTS/LIST operations are more than just "occasional" operations for data storage systems.
Again, communication issue. I wrote "occasional" in the sense of "a small set of operations", not "infrequent operations". As in, you're going through a list of all operations a DB supports, and occasionally one pops out as potentially substantially benefiting from Optane.
Regardless, your argument misses the point I'm making. The point was: how much of the total workload time do they take up. Even if Optane brought down EXISTS/LIST latency to zero, your workload (including all OS/network/client/etc. overhead) would literally have to be 90% composed of (i.e. overwhelmingly dominated by) EXISTS/LIST checks to get an order of magnitude speed improvement for the user.