disk_load: initialize array values upon first start

plugins/dynamix/nchan/disk_load

@@ -3,6 +3,15 @@ ini=/var/local/emhttp/diskload.ini
 tmp=/var/local/emhttp/diskload.tmp
 declare -a reads writes
 
+# initialize array values upon first start
+stats=($(awk '/(sd[a-z]*|nvme[0-9]*n1|vd[a-z]*) /{print $3,$6,$10,$4,$8}' /proc/diskstats))
+c=0; s=${#stats[@]}
+for ((i=0;i<s;i+=5)); do
+  reads[c]=${stats[i+1]}
+  writes[c]=${stats[i+2]}
+  ((c++))
+done
+
 # t = poll interval in seconds
 t=2
 while :; do