netisr process eats 100% cpu

[Dmitry Sivachenko]

Hello!

I am using fresh FreeBSD-10/stable.

I have a program which establish a TCP connection to server and sends a lot of small requests over it.
I put haproxy load balancer working in TCP mode in the middle, which listens some port on localhost.

Under the relatively low network load (20MB/sec, ~100 kpps), netisr process starts to consume close to 100% CPU, and does not allow to utilize more network bandwidth:

   11 root         -72    -     0K   944K CPU27  27   0:34  98.06% intr{swi1: netisr 0}

If I do not pass traffic through haproxy but connect directly to remote server, netisr process consumes 0% CPU and everything works well.

Is it rather expected or this can be fixed?

Thanks in advance.