Enhancement: slight performance improve

atom: don't call `date` to get the timestamp multiple times in the main loop

atom

@@ -708,10 +708,11 @@ echo 'BEGIN TRANSACTION;' >&3
 committime=$(date +%s)
 while (( (remaining || ${#workers[@]}) && ! quit ))
 do
-	if (( $(date +%s) - committime >= 60 ))
+	timestamp=$(date +%s)
+	if (( $timestamp - committime >= 60 ))
 	then
 		echo $'COMMIT;\nBEGIN TRANSACTION;' >&3
-		committime=$(date +%s)
+		committime=$timestamp
 	fi
 	read humanload garbage < /proc/loadavg
 	load=${humanload%.*}
@@ -721,16 +722,16 @@ do
 	else
 		if [ -z "$quit" ]					\
 		&& (( ! pause ))					\
-		&& (( $(date +%s)-concurrencychange >= loadinterval ))
+		&& (( timestamp - concurrencychange >= loadinterval ))
 		then
 			if (( concurrency > 1 ))	\
 			&& (( load > maxload ))
 			then
-				concurrencychange=$(date +%s)
+				concurrencychange=$timestamp
 				(( --concurrency ))
 			elif (( load < maxload )) && (( active > concurrency - 1 ))
 			then
-				concurrencychange=$(date +%s)
+				concurrencychange=$timestamp
 				(( ++concurrency ))
 			fi
 		fi
@@ -740,7 +741,7 @@ do
 	(( pause )) || master
 	if (( ran - failed ))
 	then
-		currenttime=$(date +%s)
+		currenttime=$timestamp
 		if (( pause ))
 		then
 			(( runtime = pausestart - starttime - pausedtime ))