not panic
keep running instead of panic during failure
reserved for future
log err before close session

otherwise, LiveServers will panic
panic: Session already closed
Merge branch 'optimization'
http interface pprof
chg watch dog signature to be more clear
rusage stats
max rss is in kb
a new profiling implementation
block profiling
output alignment
interrupt rpc server to stop
export rpc thread pool stats
use atomic instead of metrics counter

We can check rpc thread pool stats via http
profiler dir is reserved
changelog
pprof result, to bo removed
even in static pm, we still need throttle