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Comment by snihalani | Hacker News Reader

interesting. curious if anyone has benchmarked it relative to other dbs. like: https://benchmark.clickhouse.com/

CrDB is not about many many low latency queries, like say MySQL. It's designed more for getting your workload processes down to making as few large queries as every one incurs quorum latencies. You don't want to prototype something in Rails and hope there's no hidden lazy queries happening along the way.

It wouldn't be a good idea to take a large working PostgreSQL app and try to switch over to using CrDB. You'd spend all your time (unwittingly rewriting the entire app) speeding up and grouping a few queries at a time.

You can have small queries, they just have to be be sent before you block on the results from the first of each group.

We moved took a large working PostgreSQL app and switched it over to CRDB and that doesn't match my experience. Our existing schemas and query patterns moved over nicely - latency for small indexed reads and writes did increase from ~1ms to ~3ms, but the max throughput now effectively unlimited since we could add capacity by adding new nodes into the cluster and letting CRDB automatically rebalance the workload. There was an increase in cost as it will need more cores, disk etc compared to a single-primary PostgreSQL, but that makes sense when you consider that every bit of data is getting stored on 5 different nodes and there are overheads to maintain the consistency.

For the highest throughput endpoints we did make some changes to be more optimal on CRDB so we could run a smaller cluster, but it didn't require anything close to a rewrite.

That's a good story and datapoint to hear. Meanwhile upgrading one version from MySQL 5.7 to 8.0 is taking a while and will be much appreciated where I am. I don't expect any problems but wouldn't be surprised to be surprised.

Clickhouse is a totally different use case - Cockroach is OLTP, Clickhouse is OLAP. We use both Cockroach and Clickhouse at scale and they are both great but not competing products - Cockroach is great for the types of reads and writes you do when serving user requests, processing transactions etc, but isn't optimal for analytics queries where you are going do things like read and aggregate data on a 50TB table. Clickhouse eats those kinds of aggregate queries for breakfast, and is fast for some types of small read queries too, but it's not built to handle random writes or frequently updating rows of data.

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