plv8 VS postgres-benchmarks

a bit more than an experiment at this point. pljs, even in its early state, has some very good results: https://github.com/plv8/plv8/issues/531#issuecomment-1627883...

passing through v8's javascript/c++ membrane has always been painful, and appears to be getting worse.

From here you'll write a send_email function in Postgres that calls the API. I initially wrote the entire function in PLpgSQL and spent an entire day to get it debugged and working. And even then I wasn't happy with it. In my opinion that language is unintuitive and difficult to learn and debug. I switched over to PLV8, an extension for Postgres that supports writing functions in Javascript. It takes one click in the Supabase UI to enable this extension, and it will save hours and hours of time.

You jest, but the evil geniuses at plv8 have already done it for Postgresql.

To be honest I haven't used it, but I've extensively used pl/pgsql and a little pl/ruby, and know that https://plv8.github.io/ exists - it might be what you're looking for and it's on my list of things to play with

but, let's take your straw man a little further. let's suppose that all of the actual parsing is done for you already, and all you're doing is iterating through the data structure, creating objects through the c++ api, and calling it good. that should be faster than calling the c++ JSON.parse(), shouldn't it? since we don't have to actually parse anything, right? no, it's actually much slower. you can see this in action at https://github.com/plv8/plv8/blob/r3.1/plv8_type.cc#L173-L60...

again, we're not talking about whether javascript in an interpreter is faster than c++, we're talking about whether v8's api causes enough slowdown that some workloads that require a lot of data between c++ and javascript are slower than the same workload that requires very little data between c++ and javascript ... because passing through v8's c++/javascript membrane is slow.

There's a link to a simple Benchmark right after the title.

Here are two:

https://github.com/porsager/postgres-benchmarks

https://porsager.github.io/imdbench/sql.html

and really fast (https://github.com/porsager/postgres-benchmarks) even faster than the native postgres

> On the surface I'm not sure this explanation passes the smell test. Almost irrespective of how you get the data from your network card into v8 / nodejs, you're going to be crossing c++/v8 boundaries.

yes, you are, but the differences are the object creation that occurs. a single buffer coming from c/c++ (a socket, let's say) can be parsed and turned into a large number of objects in javascript much more quickly. yes, you're passing through that barrier once, but creating all of those objects from c++ and passing through it 20-30 times is a lot more expensive.

> Out of curiosity, do you have links to these other projects where they have similar benchmarking attempts/results?

how about pg vs pg-native? https://github.com/porsager/postgres-benchmarks#results

and unfortunately, I cannot find the original discussions from when node-redis went from native to pure javascript, but it was about a 30-40% speed increase originally if memory serves (I was the one who did that original conversion after a lot of deep dives into v8 and performance crossing the barrier).

as an aside, I'm also the maintainer of plv8, and am happy to discuss the same types of performance issues of dealing with jsonb vs json (which in Postgres is text): creating objects vs a simple JSON.parse() in c++ is a significant difference.