(paimon-rust) branch main updated: [core] Reuse the key buffer and row list across sort-merge keys (#1162)

[lzljs3620320]

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JingsongLi pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/paimon-rust.git


The following commit(s) were added to refs/heads/main by this push:
     new 7a446b0d [core] Reuse the key buffer and row list across sort-merge 
keys (#1162)
7a446b0d is described below

commit 7a446b0df13883cfd6751ff742e594974150a1ff
Author: JeonDaehong <90895144+jeondaeh...@users.noreply.github.com>
AuthorDate: Mon Oct 19 21:15:14 2026 +0900

    [core] Reuse the key buffer and row list across sort-merge keys (#1162)
---
 crates/paimon/src/table/sort_merge.rs | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/crates/paimon/src/table/sort_merge.rs 
b/crates/paimon/src/table/sort_merge.rs
index 9bb072e2..e43e8698 100644
--- a/crates/paimon/src/table/sort_merge.rs
+++ b/crates/paimon/src/table/sort_merge.rs
@@ -1410,6 +1410,9 @@ fn sort_merge_stream(
 
         // Output indices: (batch_buffer_idx, row_idx) for interleave.
         let mut output_indices: Vec<(usize, usize)> = 
Vec::with_capacity(batch_size);
+        // Reused for every key, so grouping allocates nothing per key.
+        let mut winner_key: Vec<u8> = Vec::new();
+        let mut same_key_rows: Vec<MergeRow> = Vec::new();
 
         loop {
             let winner_idx = tree.winner();
@@ -1418,20 +1421,20 @@ fn sort_merge_stream(
                 break;
             }
 
-            // Capture the winner's key for grouping same-key rows.
-            let winner_key = {
-                let cursor = cursors[winner_idx].as_ref().unwrap();
-                cursor.current_row().owned()
-            };
+            // Capture the winner's key for grouping same-key rows. Encoded
+            // rows compare by their bytes, so byte equality is key equality.
+            let winner = cursors[winner_idx].as_ref().unwrap();
+            winner_key.clear();
+            winner_key.extend_from_slice(winner.current_row().as_ref());
 
             // Collect all rows with the same key across all streams.
-            let mut same_key_rows: Vec<MergeRow> = Vec::new();
+            same_key_rows.clear();
 
             loop {
                 let current_winner = tree.winner();
                 let matches = match &cursors[current_winner] {
                     None => false,
-                    Some(c) => c.current_row().cmp(&winner_key.row()) == 
Ordering::Equal,
+                    Some(c) => c.current_row().as_ref() == 
winner_key.as_slice(),
                 };
                 if !matches {
                     break;