3 ms·
They're not always sitting idle waiting for one big OLAP query (well suited to parallel aggregation) to come in to exhibit a 25x speedup. Let's say you've got
by taspeotis 11y ago
They're not always sitting idle waiting for one big OLAP query (well suited to parallel aggregation) to come in to exhibit a 25x speedup.
Let's say you've got a web application with some cookie-cutter OLTP queries (which are well suited to serial plans ... no parallel aggregation benefit here). Your CPUs are running at 50% then some big OLAP query is going to come in and get maybe ... 13x faster.
Which is a nice performance improvement, but not 25x.
These numbers are a good validation of the work done in PostgreSQL, but you can't look at it and look at your X core machine, and say "my workload is going to be 25x faster!"
- ishi 11y agoThat's probably true for any benchmark - YMMV.
- pilif 11y ago> Let's say you've got a web application with some cookie-cutter OLTP queries (which are well suited to serial plans ... no parallel aggregation benefit here). in my case, the OLTP queries run against a dedicated slave that's mostly busy doing nothing, waiting for the next OLTP query to happen. So for me this will be very, very nice :-)
- taspeotis 11y agoSince I can't edit my post, the "25x speedup" I quote came from the original title of this post: "PostgreSQL Parallel Aggregate shows 25x speedup"
- mrits 11y agoIf your server is already running at 100% then there will be no speed increase!