tests: fix ceph-helpers.sh wait_for_clean delays

qa/workunits/ceph-helpers.sh

@@ -1071,6 +1071,41 @@ function test_is_clean() {
 
 #######################################################################
 
+##
+# Return a list of numbers that are increasingly larger and whose
+# total is **timeout** seconds. It can be used to have short sleep
+# delay while waiting for an event on a fast machine. But if running
+# very slowly the larger delays avoid stressing the machine even
+# further or spamming the logs.
+#
+# @param timeout sum of all delays, in seconds
+# @return a list of sleep delays
+#
+function get_timeout_delays() {
+    local -i timeout=$1
+    local -i first_step=1
+
+    local -i i
+    local -i total=0
+    for (( i = $first_step ; $total + $i <= $timeout ; i *= 2 )) ; do
+        echo -n "$i "
+        total+=$i
+    done
+    if (( $total < $timeout )) ; then
+        echo -n $(( $timeout - $total ))
+    fi
+}
+
+function test_get_timeout_delays() {
+    test "$(get_timeout_delays 1)" = "1 " || return 1
+    test "$(get_timeout_delays 5)" = "1 2 2" || return 1
+    test "$(get_timeout_delays 6)" = "1 2 3" || return 1
+    test "$(get_timeout_delays 7)" = "1 2 4 " || return 1
+    test "$(get_timeout_delays 8)" = "1 2 4 1" || return 1
+}
+
+#######################################################################
+
 ##
 # Wait until the cluster becomes clean or if it does not make progress
 # for $TIMEOUT seconds.
@@ -1080,18 +1115,12 @@ function test_is_clean() {
 # @return 0 if the cluster is clean, 1 otherwise
 #
 function wait_for_clean() {
-    local status=1
     local num_active_clean=-1
     local cur_active_clean
+    local -a delays=($(get_timeout_delays $TIMEOUT))
     local -i timer=0
-    local -i loops=0
-    local -i phase=0
     local num_pgs=$(get_num_pgs)
     test $num_pgs != 0 || return 1
-    local TENTH_TIMEOUT=($TIMEOUT * 10)
-    # The first phase 10 times (1 second) second phase an additional 15 times (15 seconds)
-    local backoff_phases=( 10 15 -1 )
-    local sleep_backoff=( .1    1   10)
 
     while true ; do
         # Comparing get_num_active_clean & get_num_pgs is used to determine
@@ -1100,21 +1129,16 @@ function wait_for_clean() {
         cur_active_clean=$(get_num_active_clean)
         test $cur_active_clean = $num_pgs && break
         if test $cur_active_clean != $num_active_clean ; then
-            timer=0 ; loops=0 ; phase=0
+            timer=0
             num_active_clean=$cur_active_clean
         elif get_is_making_recovery_progress ; then
-            timer=0 ; loops=0 ; phase=0
-        elif (( timer >= $TENTH_TIMEOUT)) ; then
+            timer=0
+        elif (( $timer >= ${#delays[*]} )) ; then
             ceph report
             return 1
         fi
-        sleep ${sleep_backoff[$phase]}
-        timer="$(echo $timer + ${sleep_backoff[$phase]} \* 10 | bc | cut -d. -f1)"
-        loops=$(expr $loops + 1)
-        if (( $loops == ${backoff_phases[$phase]} )); then
-          phase=$(expr $phase + 1)
-          loop=0
-        fi
+        sleep ${delays[$timer]}
+        timer+=1
     done
     return 0
 }