From fd9008f1239d614c347d6c316ed4f93b113d1259 Mon Sep 17 00:00:00 2001
From: Jussi Saurio <jussi.saurio@gmail.com>
Date: Mon, 6 Oct 2025 10:11:19 +0300
Subject: [PATCH] MVCC: do checkpoint writes in ascending order of rowid

For insert-heavy checkpoints this gives a much higher chance of using
the balance-quick subalgorithm instead of the more complex and slower
balance-nonroot.
---
 core/mvcc/database/checkpoint_state_machine.rs | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/core/mvcc/database/checkpoint_state_machine.rs b/core/mvcc/database/checkpoint_state_machine.rs
index a207d5ad2..7953cf2e4 100644
--- a/core/mvcc/database/checkpoint_state_machine.rs
+++ b/core/mvcc/database/checkpoint_state_machine.rs
@@ -253,6 +253,16 @@ impl<Clock: LogicalClock> CheckpointStateMachine<Clock> {
                 }
             }
         }
+        // Writing in ascending order of rowid gives us a better chance of using balance-quick algorithm
+        // in case of an insert-heavy checkpoint.
+        self.write_set.sort_by_key(|version| {
+            (
+                // Sort by table_id descending (schema changes first)
+                std::cmp::Reverse(version.0.row.id.table_id),
+                // Then by row_id ascending
+                version.0.row.id.row_id,
+            )
+        });
         self.checkpointed_txid_max_new = max_timestamp;
     }