> This write amplification is large enough that our efforts to tune indexing throughput have started to hit diminishing returns.
> don't key on the ANN address. That is precisely the change turbopuffer v3 makes. As you can imagine, it is not a trivial change.
This is a direct parallel to how Postgres and Mysql built indexes.
Your design choice went from a Postgres design pattern to a Mysql one. The difference is the reindexing cost vs the lookup cost - Postgres optimized for lookup and Mysql does for indexing on writes. Or more accurately, Postgres was better with good schema design using joins & mysql was optimized for a bad design with less normalization where many indexes exist for the same table.
Postgres always points an index to a row-id within postgres which is an arbitrary value which changes on each update.
Mysql, always assuming the storage engine is pluggable, points to the primary index entry and adds an extra indirection to the lookup.
This means that you point the mysql index to a stable id, so unless you go update the primary key for a row, you won't have to update the indexes for all the attribute lookups you might have made to data.
I don't do databases any more that much, but the design for NIMBLE file format has a lot of quirks which are relevant to this specific idea (wide tables).
But the old Uber post about switching from Postgres to Mysql to prevent index amplification[1] is a direct mirror to this post.
Many of the commenters on this site are also obviously LLMs. I'd imagine that quite a few of the entities quoting aren't necessarily people. Keep an eye on where they slide mentions of other products that a marketing team would like to promote.
Personally I haven't seen it too often; the other aspect is that HN is a forum for startups to pitch shit to each other, so this has been happening with or without marketers (f.e. "i'm working on a similar thing").
That LLMs are taking over the comments section is something that was already flagged, and Lobste.rs and others have started solving it by having gated registrations. HN should do this but it is unlikely to until it is too late.
gopalv · · focus · HN ↗
> don't key on the ANN address. That is precisely the change turbopuffer v3 makes. As you can imagine, it is not a trivial change.
This is a direct parallel to how Postgres and Mysql built indexes.
Your design choice went from a Postgres design pattern to a Mysql one. The difference is the reindexing cost vs the lookup cost - Postgres optimized for lookup and Mysql does for indexing on writes. Or more accurately, Postgres was better with good schema design using joins & mysql was optimized for a bad design with less normalization where many indexes exist for the same table.
Postgres always points an index to a row-id within postgres which is an arbitrary value which changes on each update.
Mysql, always assuming the storage engine is pluggable, points to the primary index entry and adds an extra indirection to the lookup.
This means that you point the mysql index to a stable id, so unless you go update the primary key for a row, you won't have to update the indexes for all the attribute lookups you might have made to data.
I don't do databases any more that much, but the design for NIMBLE file format has a lot of quirks which are relevant to this specific idea (wide tables).
But the old Uber post about switching from Postgres to Mysql to prevent index amplification[1] is a direct mirror to this post.
[1] - <a href="https://www.uber.com/us/en/blog/postgres-to-mysql-migration/" rel="nofollow">https://www.uber.com/us/en/blog/postgres-to-mysql-migration/
FLeXMurphy · · focus · HN ↗
0c3ca83 · · focus · HN ↗
FLeXMurphy · · focus · HN ↗
That LLMs are taking over the comments section is something that was already flagged, and Lobste.rs and others have started solving it by having gated registrations. HN should do this but it is unlikely to until it is too late.
alfiedotwtf · · focus · HN ↗
james_marks · · focus · HN ↗