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Comment by bluestreak | Hacker News Reader

Our article in question can be found here: https://questdb.io/blog/2022/05/26/query-benchmark-questdb-v...

The intent of the article was to showcase JIT-optimised WHERE clause and we did not use any indexes on QuestDB.

If your intent it to showcase the new optimization in the product it is best to compare it to your own old version

Agree. And for a blog post it can even have a story like: "We compared with ClickHouse and we were 10x slower, than we looked at this case and made it 100x faster. Thank you, benchmark and ClickHouse developers that showed us use case where we could do better."

For me benchmarking is usual - "Why this query takes so long? We need to improve it. Sometimes 1000x times."

Right? How do the folks at QuestDB know that their new JIT engine is actually responsible for those performance improvements? My understanding is that, index or not, data is still sorted by time in questdb, which is exactly what the ClickHouse engineers are replicating in the new schema.

The query Clickhouse picked on does not actually leverage time order. Perhaps clickhouse vendors on this thread can comment on relevance of the date partitioning for this query. My best guess is that it might help the execution logic to create data chunks for parallel scan.

QuestDB does also use partitions for this purpose but we also calculate chunks dynamically based on available CPU to distribute load across cores more evenly

That's fair enough and I get the broader point about ClickHouse being rather inflexible wrt query performance. It still seems like the initial sorting key for CH would've been the worst possible one for all benchmark scenarios.

Comparison with old version is actually in the article for the patient reader. It could go to the top but I don't think it will make a difference. At the end of the day it is the article at the official QuestDB website which gives the reader a spoiler about the bias.

I am intrigued what Timescale is going to publish next.

Right. The data is there but it comes with clickbait title which distracts focus from the awesome performance improvements QuestDB guys reached

> The intent of the article was to showcase JIT-optimised WHERE clause and we did not use any indexes on QuestDB.

Does not seem like it from the title.

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