tick: check tasks to cancel before checking for upgrade tasks

crates/index-scheduler/src/processing.rs

@@ -74,6 +74,7 @@ make_enum_progress! {
 make_enum_progress! {
     pub enum TaskCancelationProgress {
         RetrievingTasks,
+        CancelingUpgrade,
         UpdatingTasks,
     }
 }

crates/index-scheduler/src/scheduler/create_batch.rs

@@ -423,7 +423,8 @@ impl IndexScheduler {
     }
 
     /// Create the next batch to be processed;
-    /// 1. We get the *last* task to cancel.
+    /// 0. We get the *last* task to cancel.
+    /// 1. We get the tasks to upgrade.
     /// 2. We get the *next* task to delete.
     /// 3. We get the *next* snapshot to process.
     /// 4. We get the *next* dump to process.
@@ -443,7 +444,20 @@ impl IndexScheduler {
         let count_total_enqueued = enqueued.len();
         let failed = &self.queue.tasks.get_status(rtxn, Status::Failed)?;
 
-        // 0. The priority over everything is to upgrade the instance
+        // 0. we get the last task to cancel.
+        let to_cancel = self.queue.tasks.get_kind(rtxn, Kind::TaskCancelation)? & enqueued;
+        if let Some(task_id) = to_cancel.max() {
+            let mut task =
+                self.queue.tasks.get_task(rtxn, task_id)?.ok_or(Error::CorruptedTaskQueue)?;
+            current_batch.processing(Some(&mut task));
+            current_batch.reason(BatchStopReason::TaskCannotBeBatched {
+                kind: Kind::TaskCancelation,
+                id: task_id,
+            });
+            return Ok(Some((Batch::TaskCancelation { task }, current_batch)));
+        }
+
+        // 1. We upgrade the instance
         // There shouldn't be multiple upgrade tasks but just in case we're going to batch all of them at the same time
         let upgrade = self.queue.tasks.get_kind(rtxn, Kind::UpgradeDatabase)? & (enqueued | failed);
         if !upgrade.is_empty() {