diff --git a/include/openvswitch/json.h b/include/openvswitch/json.h
index 097bd057d..6e747f5d9 100644
--- a/include/openvswitch/json.h
+++ b/include/openvswitch/json.h
@@ -63,16 +63,28 @@ struct json_array {
     struct json **elems;
 };
 
+/* Maximum string length that can be stored inline ('\0' is not included). */
+#define JSON_STRING_INLINE_LEN (sizeof(struct json_array) - 1)
+
+enum json_storage_type {
+    JSON_STRING_DYNAMIC = 0, /* JSON_STRING is stored via 'str_ptr'. */
+    JSON_STRING_INLINE,      /* JSON_STRING is stored in 'str' array. */
+};
+
 /* A JSON value. */
 struct json {
     enum json_type type;
+    enum json_storage_type storage_type;
     size_t count;
     union {
         struct shash *object;   /* Contains "struct json *"s. */
         struct json_array array;
         long long int integer;
         double real;
-        char *string; /* JSON_STRING or JSON_SERIALIZED_OBJECT. */
+        union {
+            char str[JSON_STRING_INLINE_LEN + 1];
+            char *str_ptr;
+        }; /* JSON_STRING or JSON_SERIALIZED_OBJECT. */
     };
 };
 
diff --git a/lib/json.c b/lib/json.c
index fe223d9bc..fa92d56b3 100644
--- a/lib/json.c
+++ b/lib/json.c
@@ -179,14 +179,26 @@ struct json *
 json_string_create_nocopy(char *s)
 {
     struct json *json = json_create(JSON_STRING);
-    json->string = s;
+    json->storage_type = JSON_STRING_DYNAMIC;
+    json->str_ptr = s;
     return json;
 }
 
 struct json *
 json_string_create(const char *s)
 {
-    return json_string_create_nocopy(xstrdup(s));
+    struct json *json = json_create(JSON_STRING);
+    size_t length = strlen(s);
+
+    if (length <= JSON_STRING_INLINE_LEN) {
+        json->storage_type = JSON_STRING_INLINE;
+        memcpy(json->str, s, length);
+        json->str[length] = '\0';
+    } else {
+        json->storage_type = JSON_STRING_DYNAMIC;
+        json->str_ptr = xmemdup0(s, length);
+    }
+    return json;
 }
 
 struct json *json_string_create_uuid(const struct uuid *uuid)
@@ -198,7 +210,7 @@ struct json *
 json_serialized_object_create(const struct json *src)
 {
     struct json *json = json_create(JSON_SERIALIZED_OBJECT);
-    json->string = json_to_string(src, JSSF_SORT);
+    json->str_ptr = json_to_string(src, JSSF_SORT);
     return json;
 }
 
@@ -206,7 +218,7 @@ struct json *
 json_serialized_object_create_with_yield(const struct json *src)
 {
     struct json *json = json_create(JSON_SERIALIZED_OBJECT);
-    json->string = json_to_string(src, JSSF_SORT | JSSF_YIELD);
+    json->str_ptr = json_to_string(src, JSSF_SORT | JSSF_YIELD);
     return json;
 }
 
@@ -357,14 +369,15 @@ const char *
 json_string(const struct json *json)
 {
     ovs_assert(json->type == JSON_STRING);
-    return json->string;
+    return json->storage_type == JSON_STRING_DYNAMIC
+           ? json->str_ptr : json->str;
 }
 
 const char *
 json_serialized_object(const struct json *json)
 {
     ovs_assert(json->type == JSON_SERIALIZED_OBJECT);
-    return json->string;
+    return json->str_ptr;
 }
 
 struct json_array *
@@ -419,11 +432,13 @@ json_destroy__(struct json *json, bool yield)
         break;
 
     case JSON_STRING:
-        free(json->string);
+        if (json->storage_type == JSON_STRING_DYNAMIC) {
+            free(json->str_ptr);
+        }
         break;
 
     case JSON_SERIALIZED_OBJECT:
-        free(json->string);
+        free(json->str_ptr);
         break;
 
     case JSON_NULL:
@@ -1007,7 +1022,8 @@ json_string_escape(const char *in, struct ds *out)
 {
     struct json json = {
         .type = JSON_STRING,
-        .string = CONST_CAST(char *, in),
+        .storage_type = JSON_STRING_DYNAMIC,
+        .str_ptr = CONST_CAST(char *, in),
     };
     json_to_ds(&json, 0, out);
 }
diff --git a/python/ovs/db/data.py b/python/ovs/db/data.py
index 3e9c5049f..30a34a098 100644
--- a/python/ovs/db/data.py
+++ b/python/ovs/db/data.py
@@ -573,7 +573,8 @@ class Datum(object):
                   % (name, n)]
             for key in sorted(self.values):
                 s += ['    { .type = JSON_STRING, '
-                      '.string = "%s", .count = 2 },'
+                      '.storage_type = JSON_STRING_DYNAMIC, '
+                      '.str_ptr = "%s", .count = 2 },'
                       % escapeCString(key.value)]
             s += ["};"]
             s += ["static union ovsdb_atom %s_keys[%d] = {" % (name, n)]
@@ -592,7 +593,8 @@ class Datum(object):
                       % (name, n)]
                 for k, v in sorted(self.values):
                     s += ['    { .type = JSON_STRING, '
-                          '.string = "%s", .count = 2 },'
+                          '.storage_type = JSON_STRING_DYNAMIC, '
+                          '.str_ptr = "%s", .count = 2 },'
                           % escapeCString(v.value)]
                 s += ["};"]
                 s += ["static union ovsdb_atom %s_values[%d] = {" % (name, n)]
diff --git a/tests/test-ovsdb.c b/tests/test-ovsdb.c
index 0511e4170..ad4ca3b42 100644
--- a/tests/test-ovsdb.c
+++ b/tests/test-ovsdb.c
@@ -2413,10 +2413,13 @@ substitute_uuids(struct json *json, const struct ovsdb_symbol_table *symtab)
     if (json->type == JSON_STRING) {
         const struct ovsdb_symbol *symbol;
 
-        symbol = ovsdb_symbol_table_get(symtab, json->string);
+        symbol = ovsdb_symbol_table_get(symtab, json_string(json));
         if (symbol) {
-            free(json->string);
-            json->string = xasprintf(UUID_FMT, UUID_ARGS(&symbol->uuid));
+            if (json->storage_type == JSON_STRING_DYNAMIC) {
+                free(json->str_ptr);
+            }
+            json->storage_type = JSON_STRING_DYNAMIC;
+            json->str_ptr = xasprintf(UUID_FMT, UUID_ARGS(&symbol->uuid));
         }
     } else if (json->type == JSON_ARRAY) {
         size_t i;