fix: speed up coverage tests and LLVM tools path

.github/workflows/rust-instrumented.yml

@@ -53,7 +53,10 @@ jobs:
           cargo nextest run --locked --workspace --all-features --no-fail-fast
       - name: Generate coverage report
         run: |
+          set -euo pipefail
+          LLVM_TOOLS_BIN="$(dirname "$(rustup which llvm-profdata)")"
           grcov . --binary-path target/debug/ -s . -t lcov --llvm --ignore-not-existing \
+            --llvm-path "${LLVM_TOOLS_BIN}" \
             --threads $(nproc) \
             --ignore '../*' --ignore '/*' --ignore 'fuzz/*' --ignore 'vortex-bench/*' \
             --ignore 'home/*' --ignore 'xtask/*' --ignore 'target/*' --ignore 'vortex-error/*' \
@@ -62,6 +65,7 @@ jobs:
             --ignore 'vortex-ffi/examples/*' --ignore '*/arbitrary/*' --ignore '*/arbitrary.rs' --ignore 'vortex-cxx/*' \
             --ignore benchmarks/* --ignore 'vortex-test/*' \
             -o ${{ env.GRCOV_OUTPUT_FILE }}
+          test -s ${{ env.GRCOV_OUTPUT_FILE }}
       - name: Codecov
         uses: codecov/codecov-action@e79a6962e0d4c0c17b229090214935d2e33f8354  # v6
         with:

benchmarks-website/server/tests/landing.rs

@@ -416,11 +416,11 @@ async fn landing_page_honours_filter_query_params() -> Result<()> {
 /// full history via the explicit `/api/chart/{slug}?n=all` refetch.
 #[tokio::test]
 async fn landing_first_group_shard_caps_commits() -> Result<()> {
-    // 250 commits is comfortably above the 100-commit artifact cap so the
+    // 101 commits is the smallest fixture above the 100-commit artifact cap, so the
     // cap actually kicks in. `seed_long_history` only seeds the Random-Access
     // group; with the canonical group ordering Random Access sorts first.
     let server = Server::start().await?;
-    seed_long_history(&server, 250).await?;
+    seed_long_history(&server, 101).await?;
 
     let client = reqwest::Client::new();
     let body = client.get(server.url("/")).send().await?.text().await?;
@@ -454,7 +454,7 @@ async fn landing_first_group_shard_caps_commits() -> Result<()> {
     assert_eq!(
         commits.len(),
         100,
-        "with 250 seeded commits the shard payload should be exactly the \
+        "with 101 seeded commits the shard payload should be exactly the \
          100-commit cap; got {}",
         commits.len(),
     );

benchmarks-website/server/tests/permalinks.rs

@@ -25,7 +25,7 @@ use self::common::seed_long_history;
 #[tokio::test]
 async fn permalink_pages_default_to_latest_100_and_opt_into_full_history() -> Result<()> {
     let server = Server::start().await?;
-    seed_long_history(&server, 200).await?;
+    seed_long_history(&server, 101).await?;
 
     let chart_slug = pick_chart_slug(&server, |s| s == "Random Access").await?;
     let group_slug = pick_group_slug(&server, |s| s == "Random Access").await?;
@@ -61,7 +61,7 @@ async fn permalink_pages_default_to_latest_100_and_opt_into_full_history() -> Re
             .as_array()
             .context("all commits is array")?
             .len(),
-        200,
+        101,
         "/chart?n=all should inline the full raw history",
     );