How do people handle the OS disk partition on Hadoop or HBase nodes?

[Daniel Einspanjer]

Right now, most of our boxes have 3 disk in them.  We take a small 
partition on each of those and raid stripe them together to use as the 
OS partition then allocate the rest of the disks as JBOD for HDFS storage.

We are building out a new cluster and I'm wondering if there are any 
better ideas for balancing the need for storage and speed of the HDFS 
disks with having *some place* to put the OS and non-HDFS data.

What are other people doing about that?

-Daniel