X-Git-Url: https://git.octo.it/?p=rrdtool.git;a=blobdiff_plain;f=src%2Frrd_tune.c;h=89941dc86c6e37908a21103332c6afa8844c2a63;hp=1c80e98fefcbf17fbca8391e8c405b6d5f947966;hb=a52b72cbfa4a04d13a23225742f105595799b694;hpb=299d1636596a1911659e0a53bfad5c47e72835e0

diff --git a/src/rrd_tune.c b/src/rrd_tune.c
index 1c80e98..89941dc 100644
--- a/src/rrd_tune.c
+++ b/src/rrd_tune.c
@@ -197,15 +197,17 @@ int rrd_tune(
                 rrd_close(rrd_file);
                 return -1;
             }
-            strncpy(rrd.ds_def[ds].dst, dst, DST_SIZE - 1);
-            rrd.ds_def[ds].dst[DST_SIZE - 1] = '\0';
-
-            rrd.pdp_prep[ds].last_ds[0] = 'U';
-            rrd.pdp_prep[ds].last_ds[1] = 'N';
-            rrd.pdp_prep[ds].last_ds[2] = 'K';
-            rrd.pdp_prep[ds].last_ds[3] = 'N';
-            rrd.pdp_prep[ds].last_ds[4] = '\0';
+            /* only reset when something is changed */
+            if (strncmp(rrd.ds_def[ds].dst, dst, DST_SIZE - 1) != 0) {
+                strncpy(rrd.ds_def[ds].dst, dst, DST_SIZE - 1);
+                rrd.ds_def[ds].dst[DST_SIZE - 1] = '\0';
 
+                rrd.pdp_prep[ds].last_ds[0] = 'U';
+                rrd.pdp_prep[ds].last_ds[1] = 'N';
+                rrd.pdp_prep[ds].last_ds[2] = 'K';
+                rrd.pdp_prep[ds].last_ds[3] = 'N';
+                rrd.pdp_prep[ds].last_ds[4] = '\0';
+            }
             break;
         case 'r':
             if ((matches =