Skip to content

Comment on Optimizing writes to OLAP using buffers (ClickHouse, Redpanda, MooseStack)parent

Comments

Well yeah that's the sales pitch :)

It's a tradeoff. Analytics databases are often filled with periodic dumps of transactional databases and this feels so dirty that it's easy to accidentally forget that it isn't just a hack, it's actually a structural workaround for the poor random-write performance of analytics DBs:

OLTP = more read amplification on analytics workflows, less write amplification of random insert

OLAP = less read amplification on analytics workflows, more write amplification of random insert

If that's too theoretical, the other day I saw 1-row updates of about 10kb data lead to 1GB of writes in Redshift: 1MB block size times 300 columns times a log+shuffle factor of about 3. That's a write amplification factor of 100000. Crazy stuff.

AboutSource Built by g1lg1l

Hackerly is an independent reader for Hacker News, built on the public HN API. Not affiliated with Y Combinator.