Summary:
NOTE: there is one final pre-requisite here, which is that we should default all Mononoke binaries to `--use-mysql-client` because the other SQL client implementations will break once this lands. That said, this is probably the right time to start reviewing.
There's a lot going on here, but Tokio updates being what they are, it has to happen as just one diff (though I did try to minimize churn by modernizing a bunch of stuff in earlier diffs).
Here's a detailed list of what is going on:
- I had to add a number `cargo_toml_dir` for binaries in `eden/mononoke/TARGETS`, because we have to use 2 versions of Bytes concurrently at this time, and the two cannot co-exist in the same Cargo workspace.
- Lots of little Tokio changes:
- Stream abstractions moving to `tokio-stream`
- `tokio::time::delay_for` became `tokio::time::sleep`
- `tokio::sync:⌚:Sender::send` became `tokio::sync:⌚:Sender::broadcast`
- `tokio::sync::Semaphore::acquire` returns a `Result` now.
- `tokio::runtime::Runtime::block_on` no longer takes a `&mut self` (just a `&self`).
- `Notify` grew a few more methods with different semantics. We only use this in tests, I used what seemed logical given the use case.
- Runtime builders have changed quite a bit:
- My `no_coop` patch is gone in Tokio 1.x, but it has a new `tokio::task::unconstrained` wrapper (also from me), which I included on `MononokeApi::new`.
- Tokio now detects your logical CPUs, not physical CPUs, so we no longer need to use `num_cpus::get()` to figure it out.
- Tokio 1.x now uses Bytes 1.x:
- At the edges (i.e. streams returned to Hyper or emitted by RepoClient), we need to return Bytes 1.x. However, internally we still use Bytes 0.5 in some places (notably: Filestore).
- In LFS, this means we make a copy. We used to do that a while ago anyway (in the other direction) and it was never a meaningful CPU cost, so I think this is fine.
- In Mononoke Server it doesn't really matter because that still generates ... Bytes 0.1 anyway so there was a copy before from 0.1 to 0.5 and it's from 0.1 to 1.x.
- In the very few places where we read stuff using Tokio from the outside world (historical import tools for LFS), we copy.
- tokio-tls changed a lot, they removed all the convenience methods around connecting. This resulted in updates to:
- How we listen in Mononoke Server & LFS
- How we connect in hgcli.
- Note: all this stuff has test coverage.
- The child process API changed a little bit. We used to have a ChildWrapper around the hg sync job to make a Tokio 0.2.x child look more like a Tokio 1.x Child, so now we can just remove this.
- Hyper changed their Websocket upgrade mechanism (you now need the whole `Request` to upgrade, whereas before that you needed just the `Body`, so I changed up our code a little bit in Mononoke's HTTP acceptor to defer splitting up the `Request` into parts until after we know whether we plan to upgrade it.
- I removed the MySQL tests that didn't use mysql client, because we're leaving that behind and don't intend to support it on Tokio 1.x.
Reviewed By: mitrandir77
Differential Revision: D26669620
fbshipit-source-id: acb6aff92e7f70a7a43f32cf758f252f330e60c9