use spdlog for logging in ws + unittest + remove un-needed mutex

third_party/spdlog/bench/mem

@@ -0,0 +1,19 @@
+#!/bin/sh
+
+if [ $# -lt 1 ]; then
+  echo "usage: $0 <program>"
+fi
+
+PROG=$1
+
+if [ ! -x "$PROG" ]; then
+  echo $PROG not found or not executable.
+  exit 1
+fi
+
+$* &
+PID=$!
+
+while `kill -0 $PID 2>/dev/null`; do
+  ps -eo size,pid,user,pcpu,command --sort -size | awk '{ line=1 ; hr=$1/1024 ; printf("%13.2f Mb ",hr); } { for ( x=4 ; x<=NF ; x++ ) { printf("%s ",$x) } print "" }' | grep -v grep | grep -v $0 | grep $PROG
+done