From 54bd7b62552abe7bf116edd5f54d189ee65d64dd Mon Sep 17 00:00:00 2001
From: Noel Kwan <noelkwan1998@gmail.com>
Date: Fri, 3 Nov 2023 16:50:13 +0800
Subject: [PATCH] docs

---
 src/meta/src/barrier/progress.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/meta/src/barrier/progress.rs b/src/meta/src/barrier/progress.rs
index 66209a18812fe..25a4d4d91dff3 100644
--- a/src/meta/src/barrier/progress.rs
+++ b/src/meta/src/barrier/progress.rs
@@ -159,8 +159,11 @@ impl TrackingJob {
         }
     }
 
+    /// Returns whether the `TrackingJob` requires a checkpoint to complete.
     pub(crate) fn is_checkpoint(&self) -> bool {
         match self {
+            // Recovered tracking job is always a streaming job,
+            // It requires a checkpoint to complete.
             TrackingJob::Recovered(_) => true,
             TrackingJob::New(command) => {
                 command.context.kind.is_initial() || command.context.kind.is_checkpoint()