Month: September 2019

DDSketch: a fast and fully-mergeable quantile sketch with relative-error guarantees

~ Adrian Colyer ~ 1 Comment
DDSketch: a fast and fully-mergeable quantile sketch with relative-error guarantees Masson et al., VLDB'19 Datadog handles a ton of metrics - some customers have endpoints generating over 10M points per second! For response times (latencies) reporting a simple metric such as ‘average’ is next to useless. Instead we want to understand what’s happening at different ... Continue Reading

SLOG: serializable, low-latency, geo-replicated transactions

~ Adrian Colyer ~ 1 Comment
SLOG: serializable, low-latency, geo-replicated transactions Ren et al., VLDB'19 SLOG is another research system motivated by the needs of the application developer (aka, user!). Building correct applications is much easier when the system provides strict serializability guarantees. Strict serializability reduces application code complexity and bugs, since it behaves like a system that is running on ... Continue Reading

IPA: invariant-preserving applications for weakly consistent replicated databases

~ Adrian Colyer ~ 2 Comments
IPA: invariant-preserving applications for weakly consistent replicated databases Balegas et al., VLDB'19 IPA for developers, happy days! Last we week looked at automating checks for invariant confluence, and extending the set of cases where we can show that an object is indeed invariant confluent. I’m not going to re-cover that background in this write-up, so ... Continue Reading