netstat -m
5812/33113/38925 mbufs in use (current/cache/total)
5408/11110/16518/25600 mbuf clusters in use (current/cache/total/max)
5408/11104 mbuf+clusters out of packet secondary zone in use
(current/cache)
105/4677/4782/12800 4k (page size) jumbo clusters in use
(current/cache/total/max)
0/0/0/6400 9k jumbo clusters in use (current/cache/total/max)
0/0/0/3200 16k jumbo clusters in use (current/cache/total/max)
12689K/49206K/61895K bytes allocated to network (current/cache/total)
0/0/0 requests for mbufs denied (mbufs/clusters/mbuf+clusters)
0/0/0 requests for jumbo clusters denied (4k/9k/16k)
0/0/0 sfbufs in use (current/peak/max)
0 requests for sfbufs denied
0 requests for sfbufs delayed
441624 requests for I/O initiated by sendfile
0 calls to protocol drain routines
sockstat -4 | grep -c '.*'
6586
Так то нагрузка у вас не фиг какая, проверте не режет ли вас по полосе пропускания ваш провайдер, возможно дело в самой сетевухе.