Comment by spacemanmatt | Hacker News Reader

Comment by spacemanmatt | Hacker News Reader

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That's a lot of things.

PostgreSQL has had index organized tables (aka clustered indexes) for a long time.

I can't consider a pluggable storage engine a feature. Databases are about little except reliable storage. From memory, the only time pluggable storage drivers affected me is when I realized MyISAM was inadequate and I should have used InnoDB in the first place.

Show me meaningful benchmarks about this 2x performance advantage. Is this raw insert comparable to a local copy with triggers/constraints deferred? Odds are poor that there is such low-hanging fruit the PostgreSQL team simply ignores. My guess is you are unfamiliar with the PostgreSQL-equivalent functionality in this case.

Please don't assert "different so probably better" about MVCC implementations. That's far from rational.

Thread vs process per connection is an artifact of design. More connections don't get you more throughput, rather just consume more RAM. I'm not seeing a feature in this. Real applications pool connections whether in-app or using pgBouncer.

I don't know how you get a "general response" that people don't want "all the features" that PostgreSQL has. I've yet to find an organization using a database that doesn't experience a nearly constant feature demand as they integrate what they have and seek the next level for their operation.

I'm thinking the article is accurate, even if it seems gloating to MySQL fans.

> PostgreSQL has had index organized tables (aka clustered indexes) for a long time.

Index ordered and clustered tables are different. Postgres' CLUSTER command simply rebuilds the the index after sorting the underlying data, in a on-off, blocking, operation. That means further operations will slowly reduce the "sortedness" and that it can't be relied upon when correctness is relevant (e.g. to skip a sort step for an ORDER BY).

Real index ordered tables would be nice, but I don't see them in the near future.

> Odds are poor that there is such low-hanging fruit the PostgreSQL team simply ignores.

I'm not aware of any really low-hanging fruits that we know of. While I'd like to improve INSERT performance a bit more, I think at the moment real bottlenecks are elsewhere. I mean on a halfway good single server I can do ~240k INSERTS/sec, without pipelining and about 1100k with. That's not exactly nothing. With COPY instead of INSERTs you can do a lot more.

I think write performance can be a improved a fair bit, but it's not the low hanging fruit level anymore. The biggest things I know are 1) replacing the buffer mapping hash table with a lock free datastructure (radix tree is what I/we are experimenting with) 2) better cache replacement implementation, suitable for very large memory sizes with a high turnover 3) make buffer pins lock free (patch exists) 4) make relation extension scale better

> I'm thinking the article is accurate, even if it seems gloating to MySQL fans.

I wish we could all use a bit less adversarial tone in these kinds of discussions. Mysql does some things better. Postgres some others. For some others it's not yet clear which direction is better. Of course I personally prefer PostgreSQL, but that shouldn't make me blind that they got some things right that we didn't.

EDIT: Updated throughput number from 800k to 1.1 mio.

Just FYI, I don't primarily use MySQL and I'm much more familiar with Postgres. I don't think you read my post charitably (or correctly, in some cases: for instance, I didn't say InnoDB's MVCC implementation was better in general, just that it seemed unlikely that Postgres's is better in all cases). I listed everything I am aware of, feature-wise, that might put MySQL over Postgres for some people. I could write a far longer post in the reverse direction.

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