Chi Fujii

> > This PR looks like it's in progress, if that's the case let's keep it as a draft PR. If something is unclear, don't hesitate to ask us questions...

@peintune thanks for reporting this. Could you share more log from FerretDB please? I see that there is an error and I would like to see the stacktrace.

The error appears to come from the driver. See https://github.com/mongodb/mongo-go-driver/blob/v1/x/mongo/driver/batches.go#L17. So the request didn't reached FerretDB as the driver returned error before that. Let's see what we can do before...

That `MaxDocumentSize` is internal representation of server and not configurable for a driver. See information about `x` package https://github.com/mongodb/mongo-go-driver/tree/345ea9574e28732ca4f9d7d3bb9c103c897a65b8/x Update: I don't find implementation within FerretDB restricting maximum document size....

In fact, this is indeed configurable 🙈 The value that sets driver was the response from isMaster command's `maxBsonObjectSize` field.

> I don't see anything problematic, but should we hold to merge this once #1877 is merged (and then include tests)? I marked it as do not merge for now....

There is now one code for `saslStart`, so it's clear that `saslStart` isn't skiped, it's called either by isMaster op query or saslstart command

> The number of iterations needs to be controlled with -benchtime, otherwise it just hangs or times out. Looking at your terminal output, I don't think benchmark execution has completed....

Do we have a list of commands that sends Stable API parameters? I found this page https://www.mongodb.com/docs/manual/reference/stable-api-changelog/#std-label-stable-api-changelog

> > I ensured that PR title is good enough for the changelog. > > Please check what we have in the changelog now: https://github.com/FerretDB/FerretDB/blob/main/CHANGELOG.md It can be better :sweat:,...