Munin shows high iowait (see legend), but does not reflect it on graphs.
It has default config, except the graph_height (but the problem was from beginning, before the graph_height was chnaged).
What's wrong with it? Ububtu Oneiric 32 server.
$munin-run cpu config | grep iowait graph_order system user nice idle iowait irq softirq iowait.label iowait iowait.draw STACK iowait.min 0 iowait.type DERIVE iowait.info CPU time spent waiting for I/O operations to finish when there is nothing else to do.