Revert r587: *do* sync on clock ticks. Fix pt-stalk.t (127.1 no longer works?). Enhance --sleep-collect docs.

bin/pt-stalk

@@ -887,7 +887,6 @@ collect() {
    local start_time=$(date +'%s')
    local curr_time=$start_time
    while [ $((curr_time - start_time)) -lt $OPT_RUN_TIME ]; do
-      local ts="$(date +"TS %s.%N %F %T")"
 
       disk_space $d > $d/$p-disk-space
       check_disk_space          \
@@ -896,6 +895,9 @@ collect() {
          "$OPT_DISK_PCT_FREE"   \
          || break
 
+      sleep $(date +'%s.%N' | awk "{print $OPT_SLEEP_COLLECT - (\$1 % $OPT_SLEEP_COLLECT)}")
+      local ts="$(date +"TS %s.%N %F %T")"
+
       if [ -d "/proc" ]; then
          if [ -f "/proc/diskstats" ]; then
             (echo $ts; cat /proc/diskstats) >> "$d/$p-diskstats" &
@@ -926,7 +928,6 @@ collect() {
          (echo $ts; transactions) >>"$d/$p-transactions" &
       fi
 
-      sleep $OPT_SLEEP_COLLECT
       curr_time=$(date +'%s')
    done
    log "Loop end: $(date +'TS %s.%N %F %T')"
@@ -1996,7 +1997,9 @@ reasonably.
 
 type: int; default: 1
 
-How long to sleep between collection loop cycles.
+How long to sleep between collection loop cycles.  This is useful with
+C<--no-stalk> to do long collections.  For example, to collect data every
+minute for an hour, specify: C<--no-stalk --run-time 3600 --sleep-collect 60>.
 
 =item --socket
 

lib/bash/collect.sh

@@ -182,7 +182,6 @@ collect() {
    local start_time=$(date +'%s')
    local curr_time=$start_time
    while [ $((curr_time - start_time)) -lt $OPT_RUN_TIME ]; do
-      local ts="$(date +"TS %s.%N %F %T")"
 
       # We check the disk, but don't exit, because we need to stop jobs if we
       # need to exit.
@@ -193,6 +192,11 @@ collect() {
          "$OPT_DISK_PCT_FREE"   \
          || break
 
+      # Sleep between collect cycles.
+      # Synchronize ourselves onto the clock tick, so the sleeps are 1-second
+      sleep $(date +'%s.%N' | awk "{print $OPT_SLEEP_COLLECT - (\$1 % $OPT_SLEEP_COLLECT)}")
+      local ts="$(date +"TS %s.%N %F %T")"
+
       # #####################################################################
       # Collect data for this cycle.
       # #####################################################################
@@ -226,8 +230,6 @@ collect() {
          (echo $ts; transactions) >>"$d/$p-transactions" &
       fi
 
-      # Sleep between collect cycles.
-      sleep $OPT_SLEEP_COLLECT
       curr_time=$(date +'%s')
    done
    log "Loop end: $(date +'TS %s.%N %F %T')"

t/pt-stalk/samples/config001.conf

@@ -4,5 +4,5 @@
 --
 -umsandbox
 -pmsandbox
---host 127.1
+--host 127.0.0.1
 --port 12345