do not cache identity resolve results

2 files changed, 6 insertions, 4 deletions

diff --git a/vespalib/src/tests/net/async_resolver/async_resolver_test.cpp b/vespalib/src/tests/net/async_resolver/async_resolver_test.cpp
index 4938d2ab68e..806a7f34cbe 100644
--- a/vespalib/src/tests/net/async_resolver/async_resolver_test.cpp
+++ b/vespalib/src/tests/net/async_resolver/async_resolver_test.cpp
@@ -184,11 +184,11 @@ TEST_F("require that resolved hosts are cached", ResolveFixture()) {
     EXPECT_EQUAL(f1.get_total_cnt(), 1u);
 }
 
-TEST_F("require that host names resolving to themselves (ip addresses) are also cached", ResolveFixture()) {
+TEST_F("require that host names resolving to themselves (ip addresses) are not cached", ResolveFixture()) {
     EXPECT_EQUAL(f1.resolve("tcp/127.0.0.1:123"), "tcp/127.0.0.1:123");
     EXPECT_EQUAL(f1.resolve("tcp/127.0.0.1:456"), "tcp/127.0.0.1:456");
-    EXPECT_EQUAL(f1.get_cnt("127.0.0.1"), 1u);
-    EXPECT_EQUAL(f1.get_total_cnt(), 1u);
+    EXPECT_EQUAL(f1.get_cnt("127.0.0.1"), 2u);
+    EXPECT_EQUAL(f1.get_total_cnt(), 2u);
 }
 
 TEST_F("require that cached results expire at the right time", ResolveFixture()) {
diff --git a/vespalib/src/vespa/vespalib/net/async_resolver.cpp b/vespalib/src/vespa/vespalib/net/async_resolver.cpp
index f6e31715d06..babfcd3764d 100644
--- a/vespalib/src/vespa/vespalib/net/async_resolver.cpp
+++ b/vespalib/src/vespa/vespalib/net/async_resolver.cpp
@@ -105,7 +105,9 @@ AsyncResolver::CachingHostResolver::ip_address(const vespalib::string &host_name
         return ip_address;
     }
     ip_address = _resolver->ip_address(host_name);
-    store(host_name, ip_address);
+    if (ip_address != host_name) {
+        store(host_name, ip_address);
+    }
     return ip_address;
 }