4 ms·

It's a bit disingenuous to slap 11 9s in the first phrase of something called MemoryDB and drop "durability" after, implied by the otherwise boring durability o

It's a bit disingenuous to slap 11 9s in the first phrase of something called MemoryDB and drop "durability" after, implied by the otherwise boring durability of S3. This said, it's not bad. I'd keep in mind that the paper is one thing and putting your money where your mouth is means having an SLA for latency. So far, Google's BigTable is the only service with a read latency SLA. - 99.99 availability - 3ms p50 - 6ms P99 read-only! latency

deanCommie 2y ago
SLAs with public cloud providers don't mean what people think they mean (not saying you do, but i bet a lot of other readers do). SLAs just mean "if you can prove that we didn't meet our SLA, we'll give you a refund, and by refund we mean some % of your bill for some duration". It's not nothing - it's obviously $$s, and so teams get measured and have goals about improving their availability and latency. But most customers don't seek out those refunds, and so there is no real pressure connected between the SLA and their true performance (which is often much BETTER than the SLAs, but not because of the SLAs)
- ak217 2y ago
  > there is no real pressure connected between the SLA and their true performance I'm not sure I understand this. Regardless of the refund, if a provider cuts enough corners with SLAs, won't the customers eventually raise a stink about it and make use of the (thankfully robust) competition? Plus there's the support overhead of tracking the performance and issuing the refund, which might exceed the cost of the refund itself. I think to most people an SLA is an indicator that a company is serious about this aspect of the product's performance. Serious enough to write it into long term contracts and align its incentives to fulfill it.
broly98 2y ago
I don't understand where you got `- 3ms p50 - 6ms P99 read-only! latency ` ? https://cloud.google.com/bigtable/sla https://cloud.google.com/bigtable/sla doesn't refer to any latency SLA.

deanCommie 2y ago

SLAs with public cloud providers don't mean what people think they mean (not saying you do, but i bet a lot of other readers do). SLAs just mean "if you can prove that we didn't meet our SLA, we'll give you a refund, and by refund we mean some % of your bill for some duration". It's not nothing - it's obviously $$s, and so teams get measured and have goals about improving their availability and latency. But most customers don't seek out those refunds, and so there is no real pressure connected between the SLA and their true performance (which is often much BETTER than the SLAs, but not because of the SLAs)

ak217 2y ago
> there is no real pressure connected between the SLA and their true performance I'm not sure I understand this. Regardless of the refund, if a provider cuts enough corners with SLAs, won't the customers eventually raise a stink about it and make use of the (thankfully robust) competition? Plus there's the support overhead of tracking the performance and issuing the refund, which might exceed the cost of the refund itself. I think to most people an SLA is an indicator that a company is serious about this aspect of the product's performance. Serious enough to write it into long term contracts and align its incentives to fulfill it.

broly98 2y ago

I don't understand where you got `- 3ms p50 - 6ms P99 read-only! latency ` ? https://cloud.google.com/bigtable/sla https://cloud.google.com/bigtable/sla doesn't refer to any latency SLA.