Using a runtime with no lifo slot.

As spotted by @PSeitz, the unstealable lifo-slot is causing the
doc processor and the indexer to run on the same thread.

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ env:
   QW_TEST_DATABASE_URL: postgres://quickwit-dev:quickwit-dev@localhost:5432/quickwit-metastore-dev
   RUST_BACKTRACE: 1
   RUSTDOCFLAGS: -Dwarnings -Arustdoc::private_intra_doc_links
-  RUSTFLAGS: -Dwarnings
+  RUSTFLAGS: "--cfg tokio_unstable -Dwarnings"
 
 # Ensures that we cancel running jobs for the same PR / same workflow.
 concurrency:

.github/workflows/coverage.yml

@@ -21,6 +21,7 @@ env:
   QW_S3_ENDPOINT: "http://localhost:4566" # Services are exposed as localhost because we are not running coverage in a container.
   QW_S3_FORCE_PATH_STYLE_ACCESS: 1
   QW_TEST_DATABASE_URL: postgres://quickwit-dev:quickwit-dev@localhost:5432/quickwit-metastore-dev
+  RUSTFLAGS: "--cfg tokio_unstable"
 
 jobs:
   test:

.gitignore

@@ -22,7 +22,6 @@ QUESTIONS.txt
 .idea
 .vscode
 .vscode-license
-.cargo
 deps
 qwdata
 elastic-search-artifacts

quickwit/.cargo/config.toml

@@ -0,0 +1,2 @@
+[build]
+rustflags = ["--cfg", "tokio_unstable"]

quickwit/quickwit-common/src/runtimes.rs

@@ -92,6 +92,7 @@ fn start_runtimes(config: RuntimesConfig) -> HashMap<RuntimeType, Runtime> {
             format!("blocking-{id}")
         })
         .enable_all()
+        .disable_lifo_slot()
         .build()
         .unwrap();
     runtimes.insert(RuntimeType::Blocking, blocking_runtime);
@@ -103,6 +104,7 @@ fn start_runtimes(config: RuntimesConfig) -> HashMap<RuntimeType, Runtime> {
             format!("non-blocking-{id}")
         })
         .enable_all()
+        .disable_lifo_slot()
         .build()
         .unwrap();
     runtimes.insert(RuntimeType::NonBlocking, non_blocking_runtime);