ere are some of the usefull commands to check your server and network performance ::
To check your server memory resources for every one secconds::
watch -n 1 -d free -m
For CPU usages ::
watch -n 1 mpstat -P ALL
For Process usages ::
ps -eo pid,%cpu,vsz,args,wchan
And for the total network stats (Including SYN_RECV, ESTABLISHED etc..)
netstat -a -n|grep -E “^(tcp)”| cut -c 68-|sort|uniq -c|sort -n