diff --git a/pageserver/src/page_service.rs b/pageserver/src/page_service.rs
index e577b4221d..dc0bbb3afb 100644
--- a/pageserver/src/page_service.rs
+++ b/pageserver/src/page_service.rs
@@ -1076,6 +1076,13 @@ impl PageServerHandler {
 
             // what we want to do
             let flush_fut = pgb_writer.flush();
+            // metric for how long flushing takes
+            let flush_fut = match flushing_timer {
+                Some(flushing_timer) => {
+                    futures::future::Either::Left(flushing_timer.measure(flush_fut))
+                }
+                None => futures::future::Either::Right(flush_fut),
+            };
             // do it while respecting cancellation
             let _: () = async move {
                 tokio::select! {