diff --git a/docs/changes.xml b/docs/changes.xml
index f157e9bf..6bd30cab 100644
--- a/docs/changes.xml
+++ b/docs/changes.xml
@@ -48,6 +48,13 @@ appeared in 1.19.0.
 </para>
 </change>
 
+<change type="bugfix">
+<para>
+application processes could terminate unexpectedly under high load; the bug
+had appeared in 1.19.0.
+</para>
+</change>
+
 </changes>
 
 
diff --git a/src/nxt_unit.c b/src/nxt_unit.c
index 2cdc75f8..39e7f076 100644
--- a/src/nxt_unit.c
+++ b/src/nxt_unit.c
@@ -3606,7 +3606,10 @@ nxt_unit_wait_shm_ack(nxt_unit_ctx_t *ctx)
             return NXT_UNIT_ERROR;
         }
 
-        res = nxt_unit_ctx_port_recv(ctx, ctx_impl->read_port, rbuf);
+        do {
+            res = nxt_unit_ctx_port_recv(ctx, ctx_impl->read_port, rbuf);
+        } while (res == NXT_UNIT_AGAIN);
+
         if (res == NXT_UNIT_ERROR) {
             nxt_unit_read_buf_release(ctx, rbuf);