diff --git a/pageserver/src/pgdatadir_mapping.rs b/pageserver/src/pgdatadir_mapping.rs
index 9097a08d05..827bd29ded 100644
--- a/pageserver/src/pgdatadir_mapping.rs
+++ b/pageserver/src/pgdatadir_mapping.rs
@@ -708,20 +708,25 @@ impl<'a, T: DatadirTimeline> DatadirModification<'a, T> {
     /// Truncate relation
     pub fn put_rel_truncation(&mut self, rel: RelTag, nblocks: BlockNumber) -> Result<()> {
         ensure!(rel.relnode != 0, "invalid relnode");
-        let size_key = rel_size_to_key(rel);
+        let last_lsn = self.tline.get_last_record_lsn();
+        if self.tline.get_rel_exists(rel, last_lsn)? {
+            let size_key = rel_size_to_key(rel);
+            // Fetch the old size first
+            let old_size = self.get(size_key)?.get_u32_le();
 
-        // Fetch the old size first
-        let old_size = self.get(size_key)?.get_u32_le();
+            // Update the entry with the new size.
+            let buf = nblocks.to_le_bytes();
+            self.put(size_key, Value::Image(Bytes::from(buf.to_vec())));
 
-        // Update the entry with the new size.
-        let buf = nblocks.to_le_bytes();
-        self.put(size_key, Value::Image(Bytes::from(buf.to_vec())));
+            // Update relation size cache
+            self.tline.set_cached_rel_size(rel, self.lsn, nblocks);
 
-        // Update relation size cache
-        self.tline.set_cached_rel_size(rel, self.lsn, nblocks);
+            // Update relation size cache
+            self.tline.set_cached_rel_size(rel, self.lsn, nblocks);
 
-        // Update logical database size.
-        self.pending_nblocks -= old_size as isize - nblocks as isize;
+            // Update logical database size.
+            self.pending_nblocks -= old_size as isize - nblocks as isize;
+        }
         Ok(())
     }
 
diff --git a/test_runner/batch_others/test_fsm_truncate.py b/test_runner/batch_others/test_fsm_truncate.py
new file mode 100644
index 0000000000..0f85942598
--- /dev/null
+++ b/test_runner/batch_others/test_fsm_truncate.py
@@ -0,0 +1,11 @@
+from fixtures.log_helper import log
+from fixtures.neon_fixtures import NeonEnv, NeonEnvBuilder, NeonPageserverHttpClient
+import pytest
+
+
+def test_fsm_truncate(neon_env_builder: NeonEnvBuilder):
+    env = neon_env_builder.init_start()
+    env.neon_cli.create_branch("test_fsm_truncate")
+    pg = env.postgres.create_start('test_fsm_truncate')
+    pg.safe_psql(
+        'CREATE TABLE t1(key int); CREATE TABLE t2(key int); TRUNCATE TABLE t1; TRUNCATE TABLE t2;')
diff --git a/vendor/postgres b/vendor/postgres
index 5280b6fe10..bc6dcc493c 160000
--- a/vendor/postgres
+++ b/vendor/postgres
@@ -1 +1 @@
-Subproject commit 5280b6fe1027afd5a7e14c142913d9fdf9e2b442
+Subproject commit bc6dcc493c977f3b06ad95abf493273a693b0e12