https://www.scylladb.com/2021/04/22/on-coordinated-omission/
Also, yes, P99 CONF (https://p99conf.io) is sponsored by ScyllaDB, but we're very glad to have speakers from other NoSQL vendors like Couchbase and Redis, as well as folks from across the industry — streaming systems like Kafka (Confluent), Pulsar (Splunk), Redpanda (Vectorized). Plus storage systems like Ceph, Crimson (both Redhat) and Lightbits LightOS.
For the P99 CONF I recently conducted a quick poll of what people consider "acceptable" P99s. For some people it's <100 µseconds. For others, its <1 ms. And for some it goes all the way up to 1 second. But "acceptable" is use-case specific. An in-memory database or cache will have a very different expectation than someone writing data to SSD or even today, HDD.
33.3% of respondents expected <1 ms.
37.5% were okay with 1-<10 ms
20.8% were okay with 10-<100 ms
Only 8.3% were okay with 100ms - 1 second
(The <100 µsec was a "write-in" comment. But I am sure if I had included it, and we had a broader sample poll, you'd see it as a prevalent and vocal minority.)