diff --git a/include/sigar.h b/include/sigar.h
index ddc922ae..f6d6e90d 100644
--- a/include/sigar.h
+++ b/include/sigar.h
@@ -442,6 +442,8 @@ typedef struct {
     sigar_uint64_t rtime;
     sigar_uint64_t wtime;
     sigar_uint64_t time;
+    sigar_uint64_t snaptime;
+    double service_time;
 } sigar_disk_usage_t;
 
 /* XXX for sigar_file_system_usage_t compat */
@@ -450,6 +452,7 @@ typedef struct {
 #define disk_write_bytes disk.write_bytes
 #define disk_read_bytes disk.read_bytes
 #define disk_queue disk.queue
+#define disk_service_time disk.service_time
 
 typedef struct {
     sigar_disk_usage_t disk;
diff --git a/include/sigar_private.h b/include/sigar_private.h
index 462cefd6..64841262 100644
--- a/include/sigar_private.h
+++ b/include/sigar_private.h
@@ -312,7 +312,9 @@ int sigar_group_name_get(sigar_t *sigar, int gid, char *buf, int buflen);
 #define SIGAR_DISK_STATS_INIT(disk) \
     (disk)->reads = (disk)->writes = \
     (disk)->read_bytes = (disk)->write_bytes = \
-    (disk)->queue = (disk)->time = SIGAR_FIELD_NOTIMPL;
+    (disk)->queue = (disk)->time = \
+    (disk)->service_time = SIGAR_FIELD_NOTIMPL; \
+    (disk)->snaptime = 0
 
 #define SIGAR_DISK_STATS_NOTIMPL(fsusage) \
     SIGAR_DISK_STATS_INIT(&fsusage->disk)