Re: [ldm-users] 20080216: Nexrad Level 3 (cont.)

> OK, this was what I was trying to determine.  If your LDM was receiving
> the data in a timely manner (i.e., very low latencies and no gaps),
> this would imply that there was some sort of a problem in the
> processing of the data out our your LDM queue.  The most typical reason
> for slow processing out of an LDM queue is some sort of a bottleneck on
> the machine like high disk I/O.

Since my system looks to be mimic'ing Jeff's I can chime in and say that
it is definitely not IO related with my L3 system.

My queue file is running in a memory based file system with the entire
queue loaded into memory via a tmpfs file system.  That completely
eliminates the IO issue you would see with placing the queue on disk.

The only IO hit I take is when taking the data out of queue and writing to
disk which is dedicated to LDM data. I have no downstream feeds.

pqmon shows max age of 6902 which leads me to believe the queue size is
plenty big.

There has got to be an intermittent upstream issue somewhere. Those are
always the worst ones to troubleshoot!


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