From ada518c01562acd1e1ed5c581294344db387a526 Mon Sep 17 00:00:00 2001
From: Michal Maslanka <michal@redpanda.com>
Date: Thu, 29 Feb 2024 12:21:40 +0100
Subject: [PATCH] c/topic_table_probe: use btree_map in topic table probe

Replaced `absl::flat_hash_map` that was used in `topic_table_probe` with
the `btree_map` to avoid large allocations when we deal with large
number of topics.

Signed-off-by: Michal Maslanka <michal@redpanda.com>
(cherry picked from commit 471f0366624eff6dc19dfb1f474bc2c3c55505df)
---
 src/v/cluster/topic_table_probe.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/v/cluster/topic_table_probe.h b/src/v/cluster/topic_table_probe.h
index d1f9d080a8306..3f5bd5779c0b1 100644
--- a/src/v/cluster/topic_table_probe.h
+++ b/src/v/cluster/topic_table_probe.h
@@ -13,6 +13,7 @@
 #include "cluster/fwd.h"
 #include "ssx/metrics.h"
 
+#include <absl/container/btree_map.h>
 #include <absl/container/flat_hash_set.h>
 
 namespace cluster {
@@ -49,7 +50,7 @@ class topic_table_probe {
 
     const topic_table& _topic_table;
     model::node_id _node_id;
-    absl::flat_hash_map<model::topic_namespace, ss::metrics::metric_groups>
+    absl::btree_map<model::topic_namespace, ss::metrics::metric_groups>
       _topics_metrics;
     ss::metrics::metric_groups _internal_metrics;
     ss::metrics::metric_groups _public_metrics{