fsck recoveries, configuration

[Gary Aitken]

When my system hangs and I have to force it to power cycle, I sometimes have some fsck issues.  So some questions:

1.  It appears to me that the file system (ufs) is not writing stuff out when things are idle.  If I do a sync manually and leave the machine idle and it crashes later, it comes up clean.  If I don't do a sync manually and it crashes later, it often comes up needing fsck.  Is there a way to configure the filesystem to cache but still write cached stuff at low priority?

2.  When my machine hung (could not rlogin or ping), I powered off and rebooted.  Reboot did a deferred fsck.  After it booted I logged in, and also logged in on another system.  On the remote system I could do a ping but rlogin returned "connection reset by peer", even though I could log in locally.  I presume that is because the background fscks were not complete?

I then did a 
  ps ax | grep fsck
and saw only the "logger" process for the deferred fsck's.
I did a 
  man logger
which appeared to hang -- no output.  I'm guessing because it needed the filesystems which hadn't yet fsck'd.

I then attempted to switch consoles using
  <alt>fn
but could not.

I then attempted to kill the man logger process using ^C with no success.

Can someone shed light on the above sequence of events?  It's highly likely some of them occurred before the 60 second delay for fsck timed out, but I'd like to understand what the heck is going on.

Thanks,

Gary