server: fix iterate_count of multi_get (#215)

src/server/pegasus_server_impl.cpp

@@ -727,8 +727,6 @@ void pegasus_server_impl::on_multi_get(const ::dsn::apps::multi_get_request &req
             it->Seek(start);
             bool first_exclusive = !start_inclusive;
             while (count < max_kv_count && size < max_kv_size && it->Valid()) {
-                iterate_count++;
-
                 // check stop sort key
                 int c = it->key().compare(stop);
                 if (c > 0 || (c == 0 && !stop_inclusive)) {
@@ -747,6 +745,8 @@ void pegasus_server_impl::on_multi_get(const ::dsn::apps::multi_get_request &req
                     }
                 }
 
+                iterate_count++;
+
                 // extract value
                 int r = append_key_value_for_multi_get(resp.kvs,
                                                        it->key(),
@@ -778,8 +778,6 @@ void pegasus_server_impl::on_multi_get(const ::dsn::apps::multi_get_request &req
             bool first_exclusive = !stop_inclusive;
             std::vector<::dsn::apps::key_value> reverse_kvs;
             while (count < max_kv_count && size < max_kv_size && it->Valid()) {
-                iterate_count++;
-
                 // check start sort key
                 int c = it->key().compare(start);
                 if (c < 0 || (c == 0 && !start_inclusive)) {
@@ -798,6 +796,8 @@ void pegasus_server_impl::on_multi_get(const ::dsn::apps::multi_get_request &req
                     }
                 }
 
+                iterate_count++;
+
                 // extract value
                 int r = append_key_value_for_multi_get(reverse_kvs,
                                                        it->key(),