diff -ru pgbouncer-1.9.0_ORIG/include/bouncer.h pgbouncer-1.9.0_patch/include/bouncer.h
--- pgbouncer-1.9.0_ORIG/include/bouncer.h  2018-08-08 01:07:14.000000000 +0500
+++ pgbouncer-1.9.0_patch/include/bouncer.h  2020-01-10 19:23:25.271755325 +0500
@@ -181,6 +181,7 @@
 bool pga_pton(PgAddr *a, const char *s, int port);
 const char *pga_ntop(const PgAddr *a, char *dst, int dstlen);
 const char *pga_str(const PgAddr *a, char *dst, int dstlen);
+const char *cached_hostname(void);
 const char *pga_details(const PgAddr *a, char *dst, int dstlen);
 int pga_cmp_addr(const PgAddr *a, const PgAddr *b);
diff -ru pgbouncer-1.9.0_ORIG/src/client.c pgbouncer-1.9.0_patch/src/client.c
--- pgbouncer-1.9.0_ORIG/src/client.c  2018-07-31 00:52:16.000000000 +0500
+++ pgbouncer-1.9.0_patch/src/client.c  2020-01-10 19:23:57.421246389 +0500
@@ -413,7 +413,7 @@

     /* add details */
     details = pga_details(&client->remote_addr, abuf, sizeof(abuf));
-    snprintf(buf, sizeof(buf), "%s - %s", app_name, details);
+    snprintf(buf, sizeof(buf), "%s - %s [%s]", app_name, details, cached_hostname());
     app_name = buf;
   }
   if (app_name) {
diff -ru pgbouncer-1.9.0_ORIG/src/util.c pgbouncer-1.9.0_patch/src/util.c
--- pgbouncer-1.9.0_ORIG/src/util.c  2018-07-27 02:43:02.000000000 +0500
+++ pgbouncer-1.9.0_patch/src/util.c  2020-01-10 19:23:04.822079311 +0500
@@ -414,7 +414,7 @@
   return dst;
 }

-static const char *cached_hostname(void)
+const char *cached_hostname(void)
 {
   static char cache[256];
   int err;