Netperf is a cool little utility that I discovered while working with Crossbow. It's technically a network benchmarking tool, but it's fun to use to hammer your network with load and test out Crossbow's bandwidth control features.

Simply click the link to install netperf , which will launch the Package Manager Web Installer:

To verify the installation, first start the benchmark server:

bleonard@opensolaris:~$ netserver
Starting netserver at port 12865
Starting netserver at hostname 0.0.0.0 port 12865 and family AF_UNSPEC

Then run netperf, which will run a TCP_STREAM test of 10 seconds over the loopback interface:

bleonard@opensolaris:~$ netperf
TCP STREAM TEST from ::ffff:0.0.0.0 (0.0.0.0) port 0 AF_INET to opensolaris (127.0.0.1) port 0 AF_INET
Recv   Send    Send                          
Socket Socket  Message  Elapsed              
Size   Size    Size     Time     Throughput  
bytes  bytes   bytes    secs.    10^6bits/sec  

 49152  49152  49152    10.00    4895.46  

Now that we know Netperf is set up correctly, we can use it to test bulk data transfer performance between 2 hosts (or 2 zones). TCP stream performance is the default test type and it's simply performed by running the command:

netperf -H <remotehost>

which will run a 10 second test between the local and remote system.

So I'm going to use netperf to run some tests between the global zone and a local zone, which has been set up to use a Crossbow virtual NIC exclusively. To create such a configuration on your own, see the blog entry Zones and Crossbow.

The local zone, myzone, is currently up and running:

bleonard@opensolaris:~$ zoneadm list -cv
  ID NAME             STATUS     PATH                           BRAND    IP    
   0 global           running    /                              native   shared
   - myzone           running    /zones/myzone                  ipkg     excl 

The first thing I'm going to do is copy the netserver program over to the local zone:

pfexec cp /opt/csw/bin/netserver /zones/myzone/root/var/tmp/.

And then start the netserver:

bleonard@opensolaris:~$ pfexec zlogin myzone /var/tmp/netserver
en_US.UTF-8: unknown locale
en_US.UTF-8: unknown locale
Starting netserver at port 12865
Starting netserver at hostname 0.0.0.0 port 12865 and family AF_UNSPEC

Now let's test the connection between the global and local zone:

bleonard@opensolaris:~$ netperf -H 10.0.1.25
TCP STREAM TEST from ::ffff:0.0.0.0 (0.0.0.0) port 0 AF_INET to ::ffff:10.0.1.25 (10.0.1.25) port 0 AF_INET
Recv   Send    Send                          
Socket Socket  Message  Elapsed              
Size   Size    Size     Time     Throughput  
bytes  bytes   bytes    secs.    10^6bits/sec  

 49152  49152  49152    10.00    1130.01   

Here we can see the throughput between my zones is 1130 Mbit/s. Now let's reduce the max bandwidth of the virtual NIC to 500 Mbit/s and try the test again:

bleonard@opensolaris:~$ pfexec dladm set-linkprop -p maxbw=500 myzone0
bleonard@opensolaris:~$ dladm show-vnic
LINK         OVER         SPEED  MACADDRESS           MACADDRTYPE         VID
myzone0      e1000g0      500    2:8:20:59:0:b5       random              0
bleonard@opensolaris:~$ netperf -H 10.0.1.25
TCP STREAM TEST from ::ffff:0.0.0.0 (0.0.0.0) port 0 AF_INET to ::ffff:10.0.1.25 (10.0.1.25) port 0 AF_INET
Recv   Send    Send                          
Socket Socket  Message  Elapsed              
Size   Size    Size     Time     Throughput  
bytes  bytes   bytes    secs.    10^6bits/sec  

 49152  49152  49152    10.00     486.22   

Or at a ridiculously low 2 Mbit/s:

bleonard@opensolaris:~$ pfexec dladm set-linkprop -p maxbw=2 myzone0
bleonard@opensolaris:~$ netperf -H 10.0.1.25
TCP STREAM TEST from ::ffff:0.0.0.0 (0.0.0.0) port 0 AF_INET to ::ffff:10.0.1.25 (10.0.1.25) port 0 AF_INET
Recv   Send    Send                          
Socket Socket  Message  Elapsed              
Size   Size    Size     Time     Throughput  
bytes  bytes   bytes    secs.    10^6bits/sec  

 49152  49152  49152    10.25       1.09   

Good stuff.

I've just scratched the surface of Netperf, but this simple introduction suits my purposes for testing Crossbow. For more fun check out the Netperf manual.