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[LDM #OJL-403914]: LDM Memory Issues

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  • Subject: [LDM #OJL-403914]: LDM Memory Issues
  • Date: Mon, 11 Jul 2011 10:22:24 -0600
Justin,

> I'm having an issue with LDM (6.9.8) memory usage on a "cloud" server running 
> CentOS5.5, specifically Linux 2.6.18-194.26.1.el5xen.  First a little 
> background of what we are trying to do...
> We established a private NOAAPort connection so that we could have available 
> a reliable, non-NWS network data flow for several reasons, some work related 
> and some not.  You folks solved a problem we were seeing with the 
> NGRID/NEXRAD3 flow dropping out of our NOAAPort ingestors back a couple of 
> months ago (vortex.servebeer.com).  Thanks to you, our NOAAPort ingest has 
> worked flawlessly since your assistance.

Glad to help.

> Now we are attempting to have that data served off of a high 
> availability/high bandwidth "cloud" server from a web hosting company that I 
> have dealt with for years.  The problem we are seeing is when we fire up ldm, 
> an ldmd process and pqact process start munching memory until the machine is 
> brought to it's knees (monitoring via "top" command).  We are only Requesting 
> NEXRAD3 data from vortex.servebeer.com, not the entire NOAAPort feed.
> Anyhow, I've searched mail lists, etc, and haven't found this problem 
> specifically.  I've worked with ldm on many different machines for several 
> years and have never seen this issue.  If you guys are willing to take a look 
> at this, I would be very appreciative.  Similar to my issues with our vortex 
> machine, I have absolutely no problem giving you full access to the machine 
> to troubleshoot.  Of course, alternatively, I would be more than happy to get 
> you logs/other config question info, etc.  Otherwise, I'm at a loss of what 
> to do.  Thanks for your consideration.

I think this is the second time I've heard of a "memory leak" in the LDM on a 
"cloud" system. Is the system in question virtual or physical? If it's virtual, 
then I can't help but think that there might be a bug in the virtualization 
system because we don't see any memory leaks on actual systems.

Since this is new and we don't know what we're looking for, would you please 
send the information necessary to log onto the system in question as the LDM 
user.

> Justin Weaver

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: OJL-403914
Department: Support LDM
Priority: Normal
Status: Closed