From 4d7c3d0f2e6af0d58f6daa902fe5425ec47b0c19 Mon Sep 17 00:00:00 2001
From: Moritz Hoffmann <antiguru@gmail.com>
Date: Wed, 22 Nov 2023 19:58:42 -0500
Subject: [PATCH] Only retain two allocations

This fixes retaining memory as large as the output when sealing the merge
batcher for columnation.

Signed-off-by: Moritz Hoffmann <antiguru@gmail.com>
---
 src/trace/implementations/merge_batcher_col.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/trace/implementations/merge_batcher_col.rs b/src/trace/implementations/merge_batcher_col.rs
index 3b1d5eaec..961cfa186 100644
--- a/src/trace/implementations/merge_batcher_col.rs
+++ b/src/trace/implementations/merge_batcher_col.rs
@@ -203,7 +203,7 @@ impl<D: Ord+Clone+Columnation+'static, T: Ord+Clone+Columnation+'static, R: Semi
 
     /// Insert an empty buffer into the stash. Panics if the buffer is not empty.
     fn recycle(&mut self, mut buffer: TimelyStack<(D, T, R)>) {
-        if buffer.capacity() == Self::buffer_size() {
+        if buffer.capacity() == Self::buffer_size() && self.stash.len() <= 2 {
             buffer.clear();
             self.stash.push(buffer);
         }