Compare site: cache master-branch Rust commits to improve performance

Author: miwig

collector/src/lib.rs

@@ -265,8 +265,7 @@ pub struct MasterCommit {
 /// Note that this does not contain try commits today, so it should not be used
 /// to validate hashes or expand them generally speaking. This may also change
 /// in the future.
-pub async fn master_commits() -> Result<Vec<MasterCommit>, Box<dyn std::error::Error + Sync + Send>>
-{
+pub async fn master_commits() -> anyhow::Result<Vec<MasterCommit>> {
     let response = reqwest::get("https://triage.rust-lang.org/bors-commit-list").await?;
     Ok(response.json().await?)
 }

site/src/comparison.rs

@@ -25,9 +25,10 @@ pub async fn handle_triage(
     log::info!("handle_triage({:?})", body);
     let start = body.start;
     let end = body.end;
-    let master_commits = collector::master_commits()
+    ctxt.update_master_commits()
         .await
         .map_err(|e| format!("error retrieving master commit list: {}", e))?;
+    let master_commits = &ctxt.master_commits.load().commits;
 
     let start_artifact = ctxt
         .artifact_id_for_bound(start.clone(), true)
@@ -95,20 +96,22 @@ pub async fn handle_compare(
     ctxt: &SiteCtxt,
 ) -> api::ServerResult<api::comparison::Response> {
     log::info!("handle_compare({:?})", body);
-    let master_commits = collector::master_commits()
+    ctxt.update_master_commits()
         .await
         .map_err(|e| format!("error retrieving master commit list: {}", e))?;
+    let master_commits = &ctxt.master_commits.load().commits;
+
     let end = body.end;
     let comparison =
-        compare_given_commits(body.start, end.clone(), body.stat, ctxt, &master_commits)
+        compare_given_commits(body.start, end.clone(), body.stat, ctxt, master_commits)
             .await
             .map_err(|e| format!("error comparing commits: {}", e))?
             .ok_or_else(|| format!("could not find end commit for bound {:?}", end))?;
 
     let conn = ctxt.conn().await;
-    let prev = comparison.prev(&master_commits);
-    let next = comparison.next(&master_commits);
-    let is_contiguous = comparison.is_contiguous(&*conn, &master_commits).await;
+    let prev = comparison.prev(master_commits);
+    let next = comparison.next(master_commits);
+    let is_contiguous = comparison.is_contiguous(&*conn, master_commits).await;
     let benchmark_map = conn.get_benchmarks().await;
 
     let comparisons = comparison
@@ -455,7 +458,9 @@ pub async fn compare(
     stat: String,
     ctxt: &SiteCtxt,
 ) -> Result<Option<Comparison>, BoxedError> {
-    let master_commits = collector::master_commits().await?;
+    ctxt.update_master_commits().await?;
+    let master_commits = &ctxt.master_commits.load().commits;
+
     compare_given_commits(start, end, stat, ctxt, &master_commits).await
 }
 

site/src/load.rs

@@ -4,13 +4,14 @@ use std::fs;
 use std::ops::RangeInclusive;
 use std::path::Path;
 use std::sync::Arc;
+use std::time::Instant;
 
 use anyhow::Context;
 use chrono::{Duration, Utc};
 use serde::{Deserialize, Serialize};
 
 use crate::db;
-use collector::Bound;
+use collector::{Bound, MasterCommit};
 use database::Date;
 
 use crate::api::github;
@@ -100,6 +101,23 @@ pub struct Config {
     pub keys: Keys,
 }
 
+#[derive(Debug)]
+pub struct MasterCommitCache {
+    pub commits: Vec<MasterCommit>,
+    pub updated: Instant,
+}
+
+impl MasterCommitCache {
+    /// Download the master-branch Rust commit list
+    async fn download() -> anyhow::Result<Self> {
+        let commits = collector::master_commits().await?;
+        Ok(Self {
+            commits,
+            updated: Instant::now(),
+        })
+    }
+}
+
 /// Site context object that contains global data
 pub struct SiteCtxt {
     /// Site configuration
@@ -108,6 +126,8 @@ pub struct SiteCtxt {
     pub landing_page: ArcSwap<Option<Arc<crate::api::graphs::Response>>>,
     /// Index of various common queries
     pub index: ArcSwap<crate::db::Index>,
+    /// Cached master-branch Rust commits
+    pub master_commits: ArcSwap<MasterCommitCache>,
     /// Database connection pool
     pub pool: Pool,
 }
@@ -160,9 +180,12 @@ impl SiteCtxt {
             }
         };
 
+        let master_commits = MasterCommitCache::download().await?;
+
         Ok(Self {
             config,
             index: ArcSwap::new(Arc::new(index)),
+            master_commits: ArcSwap::new(Arc::new(master_commits)),
             pool,
             landing_page: ArcSwap::new(Arc::new(None)),
         })
@@ -199,6 +222,16 @@ impl SiteCtxt {
             all_commits,
         )
     }
+
+    /// Download master-branch Rust commits if the cached value is older than one minute
+    pub async fn update_master_commits(&self) -> anyhow::Result<()> {
+        let commits = self.master_commits.load();
+        if commits.updated.elapsed() > std::time::Duration::from_secs(60) {
+            self.master_commits
+                .store(Arc::new(MasterCommitCache::download().await?))
+        }
+        Ok(())
+    }
 }
 
 /// Calculating the missing commits.

site/src/server.rs

@@ -277,6 +277,8 @@ impl Server {
         // Refresh the landing page
         ctxt.landing_page.store(Arc::new(None));
 
+        let _ = ctxt.update_master_commits().await;
+
         // Spawn off a task to post the results of any commit results that we
         // are now aware of.
         tokio::spawn(async move {