title: FreeBSD iostat - How to tell if there's a problem?
body: <p>I run a FreeBSD NFS server and recently I've been having odd issues throughout the cluster (the Apache servers are hanging in "lockf" state when loading files from the NFS share, etc).</p>
  
  <p>I'm fairly new to this, so my question is how can I tell if a server's IO is getting overloaded?</p>
  
  <p>Here is my current iostat:</p>
  
  <pre>
  [root@host ~]# iostat 1 10  
        tty           mfid0             cpu  
   tin tout  KB/t tps  MB/s  us ni sy in id  
     0   55 16.03 194  3.04   0  0  5  0 95  
     0  490 21.73 238  5.05   0  0  5  0 95  
     0   43 20.09 402  7.88   0  0  7  0 93  
     0  407 12.58 531  6.53   0  0  5  0 94  
     0   43 15.69 416  6.37   0  0  8  1 91  
     0  437 30.23 287  8.46   0  0  9  1 91  
     0   43 23.50 109  2.50   0  0  2  0 98  
     0  273 11.58  76  0.86   0  0  2  0 98  
     0   43 15.70 243  3.72   0  0  5  0 95  
     0  320 20.35 248  4.92   0  0  3  0 96  
  [root@host ~]#
  </pre>
  
  <p>Do any of the values seem high?  Are there any other tests I can do to see if the system is handling the load efficiently?</p>
  
  <p>Thanks!</p>