From 17bbbcb44d8cd4331449313fea93ad8efdf73306 Mon Sep 17 00:00:00 2001
From: Ashley Coleman <ashley.coleman@sifive.com>
Date: Tue, 30 Jul 2024 11:12:26 -0600
Subject: [PATCH] rsc: Allow config for chunking blob eviction + no sleep until
 caught up (#1610)

---
 rust/rsc/src/bin/rsc/main.rs | 46 ++++++++++++++++++++----------------
 rust/rsc/src/database.rs     |  3 ++-
 2 files changed, 28 insertions(+), 21 deletions(-)

diff --git a/rust/rsc/src/bin/rsc/main.rs b/rust/rsc/src/bin/rsc/main.rs
index cdf23c36c..9785b865e 100644
--- a/rust/rsc/src/bin/rsc/main.rs
+++ b/rust/rsc/src/bin/rsc/main.rs
@@ -227,33 +227,41 @@ fn launch_job_eviction(conn: Arc<DatabaseConnection>, tick_interval: u64, ttl: u
 
 fn launch_blob_eviction(
     conn: Arc<DatabaseConnection>,
-    tick_interval: u64,
-    setup_ttl: u64,
+    config: Arc<config::RSCConfig>,
     blob_stores: HashMap<Uuid, Arc<dyn blob::DebugBlobStore + Sync + Send>>,
 ) {
-    // TODO: This should probably be a transaction so that a job can't add a new reference to a
-    // blob as we are deleting it.
-
     tokio::spawn(async move {
-        let mut interval = tokio::time::interval(Duration::from_secs(tick_interval));
+        let mut interval =
+            tokio::time::interval(Duration::from_secs(config.blob_eviction.tick_rate));
+        let mut should_sleep = false;
         loop {
-            interval.tick().await;
             tracing::info!("Blob TTL eviction tick");
+            if should_sleep {
+                interval.tick().await;
+            }
 
             // Blobs must be at least this old to be considered for eviction.
             // This gives clients time to reference a blob before it gets evicted.
-            let setup_ttl = (Utc::now() - Duration::from_secs(setup_ttl)).naive_utc();
+            let ttl = (Utc::now() - Duration::from_secs(config.blob_eviction.ttl)).naive_utc();
 
-            let blobs = match database::read_unreferenced_blobs(conn.as_ref(), setup_ttl).await {
+            let blobs = match database::read_unreferenced_blobs(
+                conn.as_ref(),
+                ttl,
+                config.blob_eviction.chunk_size,
+            )
+            .await
+            {
                 Ok(b) => b,
                 Err(err) => {
                     tracing::error!(%err, "Failed to fetch blobs for eviction");
+                    should_sleep = true;
                     continue; // Try again on the next tick
                 }
             };
 
             let blob_ids: Vec<Uuid> = blobs.iter().map(|blob| blob.id).collect();
             let eligible = blob_ids.len();
+            should_sleep = eligible == 0;
 
             tracing::info!(%eligible, "At least N blobs eligible for eviction");
 
@@ -262,6 +270,7 @@ fn launch_blob_eviction(
                 Ok(deleted) => tracing::info!(%deleted, "Deleted blobs from database"),
                 Err(err) => {
                     tracing::error!(%err, "Failed to delete blobs from db for eviction");
+                    should_sleep = true;
                     continue; // Try again on the next tick
                 }
             };
@@ -317,11 +326,6 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let config = config::RSCConfig::new()?;
     let config = Arc::new(config);
 
-    if args.show_config {
-        println!("{}", serde_json::to_string_pretty(&config).unwrap());
-        return Ok(());
-    }
-
     // setup a subscriber for logging
     let _guard = if let Some(log_directory) = config.log_directory.clone() {
         let file_appender = tracing_appender::rolling::daily(log_directory, "rsc.log");
@@ -334,6 +338,13 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         None
     };
 
+    let config_json = serde_json::to_string_pretty(&config).unwrap();
+    if args.show_config {
+        println!("{}", config_json);
+        return Ok(());
+    }
+    tracing::info!(%config_json, "Launching RSC with config");
+
     // Increase the number of allowed open files the the max
     request_max_fileno_limit();
 
@@ -352,12 +363,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         config::RSCJobEvictionConfig::LRU(_) => panic!("LRU not implemented"),
     }
 
-    launch_blob_eviction(
-        connection.clone(),
-        config.blob_eviction.tick_rate,
-        config.blob_eviction.ttl,
-        stores.clone(),
-    );
+    launch_blob_eviction(connection.clone(), config.clone(), stores.clone());
 
     // Launch the server
     let router = create_router(connection.clone(), config.clone(), &stores);
diff --git a/rust/rsc/src/database.rs b/rust/rsc/src/database.rs
index da7d18e51..cd3c12671 100644
--- a/rust/rsc/src/database.rs
+++ b/rust/rsc/src/database.rs
@@ -626,6 +626,7 @@ pub async fn upsert_blob<T: ConnectionTrait>(
 pub async fn read_unreferenced_blobs<T: ConnectionTrait>(
     db: &T,
     ttl: NaiveDateTime,
+    chunk: u32,
 ) -> Result<Vec<blob::Model>, DbErr> {
     // Limit = 16k as the query is also subject to parameter max.
     // Blob has 4 params so (2^16)/4 = 16384. Also generally best to chunk blob eviction
@@ -648,7 +649,7 @@ pub async fn read_unreferenced_blobs<T: ConnectionTrait>(
             )
             LIMIT $2
             "#,
-            [ttl.into(), (MAX_SQLX_PARAMS / 4).into()],
+            [ttl.into(), chunk.into()],
         ))
         .all(db)
         .await