[TriLUG] System overload issues

[Brian McCullough]

On Fri, May 24, 2013 at 11:46:06AM -0400, Ron Kelley wrote:
> (First reply is held up by the moderators - message too long)...
> 
> Brian,
> 
> From the sar output, the system is really getting hammered between midnight and 8:30am (extremely high I/O wait and high CPU).  I suspect you are running out of RAM and are swapping like crazy during this time.  From 9am until 6PM (normal business hours), the box seems to be handling the load very well with little I/O wait and relatively hight %idle numbers.  It is strange your issues are during the daytime when the system is mostly idle instead of at night...

Sorry, Ron.  I guess I mis-spoke.  The big outage was exactly during
this time, midnight-9am.

There are much shorter outages randomly throughout the day, but a lot of
the bigger outages are either between midnight and 7am, or in the
evening, oddly enough.


Thank you all for your insights.  Since the machine is in a server farm
in Ann Arbor, I don't have physical contact with it, but I will be
consulting with the people there about some of these concerns, too.


I will report back when I have more to discuss.


Brian