What sort of things are people doing in their SQL queries that make them CPU bound? Admittedly I'm a meat-and-potatoes guy, but I like mine I/O bound.

Really amazed to see not one but several generic JIT frameworks though, no idea that was a thing.

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vladich an hour ago | parent | next [-]

Most databases in practice are sub-terabyte and even sub-100Gb, their active dataset is almost fully cached. For most databases I worked with, cache hit rate is above 95% and for almost all of them it's above 90%. In that situation, most queries are CPU-bound. It's completely different from typical OLAP in this sense.

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martinald 5 hours ago | parent | prev | next [-]

Anything jsonb in my experience is quickly CPU bound...

	▲	jjice 16 minutes ago \| parent [-]
		Definitely. If you're doing regular queries with filters on jsonb columns, having the index directly on the JSON paths is really powerful. If I have a jsonb filter in the codebase at all, it probably needs an index, unless I know the result set is already very small.

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5 hours ago | parent | prev | next [-]

[deleted]

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wreath 4 hours ago | parent | prev | next [-]

I think reading queries that are always served from cache are CPU bound because it also involves locking the buffers etc and there is no I/O involved.

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throwaway140126 5 hours ago | parent | prev [-]

PostgreSQL is Turing complete, so I guess they do what ever they want?