wanderinglight

You weren't in the know then. But it's encouraging to know that this is not widespread.

Formations in Ketu rely on knowing where nodes need to be placed and which slots in a formation are not filled.

Once this is known we translate the nodes towards the assigned slot in each step.

When you say "which nodes are rotationally reachable", what does that imply for formations? A node will be assigned a slot and has to move towards it while trying to avoid obstacles.

Happy to take a look if you file an issue on Ketu with details.

I don't have any experience with Lua but looking around I think it should be easy to load the formation coordinator / node implementations as Lua files that can be hot reloaded without re-compiling.

Great suggestion! I've created an issue to keep track of this. https://github.com/sushrut141/ketu/issues/8

I will definitely look into this once Ketu gains more traction. REPLit like behaviour would help more people try things out.

Thanks, I updated the description in the README to make it more clear. Feel free to create an issue on the repo if anything is unclear!

I like the idea. I"m not able to understand how quaternions alone can be used to navigate through space without a position translation vector.

The uses cases in the docs for drone control and manipulating kinetic arms with multiple degrees of freedom look promising though.

What does SpinStep provide? - Is it a traversal framework for quaternions? - Or it is a constraint solver that computes a series of transformations to make each node in a scene comply with a final end state

If it can be used for translating nodes as well via quaternions I would be interested in implementing a formation coordinator for it.

If you have an idea of what quaternion transformation will help achieve in Ketu and what the end state looks like please do create an issue on the Repo. I'll see if I can implement it using the concepts in SpinStep.

We let the generator code hardcore the weight into the generated source.

GPU performance significantly affects performance by as much as 20X. This project is only intended for cases where GPU is not available / desired due to cost or other constraints,

This is great, thank so much! I'll see if I can I can integrate this and how it compares to parquet_fdw.

This is definitely something I intend to fix.

My initial intent was to use duckdb for fast vectored query execution but I wasn't able to create a planner / execution hook that uses duckdb internally. Will definitely checkout pg_analytics / Datafusion to see if the same can be integrated here as well. Thanks for the pointers.

I looked into pg_analytics and some other solution like Citus before working on pg_analytica.

The key difference is solutions like pg_analytics completely swap out the native postgres row based storage for columnar storage.

Not using the default postgres storage engine means you miss outon a lot of battle tested, functionality like updating existing rows, deleting rows, transactional updates etc. Columnar stores are not suited for transactions, updates and deletes.

pg_analytica retains the existing Postgres storage and only exports a time delayed version of the table in columnar format. This way developers get the benefit of a transactional storage and fast analytics queries.

Hey Fabian, there are indeed many trade-offs in making this possible.

The extension periodically schedules export runs for a table exporting all the data each time (I know this is expensive but I haven't found an alternative like a change pump for getting writes after time T in Postgres yet). The export frequency can be configured by the user.

Regarding how much the delay will be, we that depends on the export frequency and the machine running the Postgres instance. A fast machine could complete an entire table export every hour or so resulting data that is decently fresh. Slower / more resource constrained machines would have to schedule exports at a slower frequency.

This lecture series on columnar storage formats and querying them is great. https://youtu.be/1hdynBJo3ew?si=5KfT_2qpUFQmy_uL

Introducing the pg_analytica extension for Postgres.

Tables can be exported to columnar format via this extension to massively speed up your analytics queries. Exported data is periodically refreshed to keep your query results fresh.