Hostmon Out of System Resources

KS-Soft · Post by **KS-Soft** » Fri Apr 08, 2005 11:54 am

I don't think it is the type of report, but the ammount of reports that needs to be generated.

If single report did not produce resource leakage, 1000 reports will not produce resource leakage either.
When I tested HostMonitor, I did not sit and wait for error message, I simply checked resources allocation and release. HostMonitor closes all handles, files and releases all memory used by report generator. So resource usage before and after report generation looks exactly the same.

Anyway, I will try to test it again using your settings. Probably problem not in the report module at all.

Regards
Alex

Marcus · Post by **Marcus** » Sat Apr 09, 2005 8:38 am

So resource usage before and after report generation looks exactly the same

Like I said, HostMonitor does not stop. If HostMonitor is running as a service, there are no pop message so everything should be the same after report generation is finished.

KS-Soft · Post by **KS-Soft** » Sat Apr 09, 2005 11:52 am

Marcus,

Sorry, I do not understand what you want to say. You experience the problem or do not? Should I investigate this problem or not?
What the difference - monitor stops or doesn't? If problem exists, it should be fixed.

there are no pop message so everything should be the same after report generation is finished

May be you think only windows can use resources of the system? Actually its more complicated. E.g. if HostMonitor opens the file but does not close it, there is resource leakage. If HostMonitor allocates some memory but does not release it, there is resource leakage. And so on...

Regards
Alex

Marcus · Post by **Marcus** » Sun Apr 10, 2005 5:30 am

What I mean is the following:

When I run HostMonitor as a service, it wil not have the right to generate a pop-up menu (interaction with the desktop is not possible). And if they would appear on the desktop, I wil never see them, using a terminal service session.

When I run HostMonitor as an application, it has the right to generate a pop-up menu (interaction wiht the desktop is possible).

So I only "see" the pop-up messages when I start HostMonitor as an application. But in both cases, I get the same message in the event viewer and I do not know if the last report generated is the correct one! (most likely not). So yes this should be investigated. Especially since Windows itself has no lack of memory!

Since multiple pop-up messages appear, it is obvious that HostMonitor itself does not stop. This means that comparing resource usage before and after the (non-generated) pop-up messages (if HostMonitor is running as a service) should not result in any 'leakage'.

I never said it was a memory leak

But perhaps one part of the application needs more but doesn't request or get more memory. And be assured, I do know how resource allocation works and also how you can mess up a system when you incorrectly work with it

timn · Post by **timn** » Mon Apr 11, 2005 8:17 am

Alex:

Sorry, I believe I was the one who suggested a memory leak, but this was just a WAG (wild ass guess) on my part. Indeed, our experience here is very close to that described by Marcus. We generally run HM as application.

It may be that the error message is a bit misleading and that the error has nothing to do with memory.

When the error does occur, we generally get several instances of the error dialog box on the screen - sorry but I can't tell you how often a new instance pops up.

This situation actually happened again over the weekend. But I was not here - I had to walk the weekend tech guy through a simple reboot over the phone. I was not able to gather any additional info.

It will probably be at least 2 weeks before this problem happens again -- but I will try to set up some basic monitoring of memory usage on the HM machine. Let me know if there is something specific you want me to keep track of.

sadek76 · Post by **sadek76** » Mon Apr 11, 2005 9:57 am

Alex,

I just had the problem happen on a 2000 server-SP3, running ver. 5.12. I sent snapshots and log files to you. I can leave the system in this state for a little while, let me know if you need anything else, before I restart the service.

Also, All - Please check your Event Viewer (App Log) when you receive the error. I receive a entry from hostmon about Access violation 005E6A72, Read address: 00000047.

KS-Soft · Post by **KS-Soft** » Mon Apr 11, 2005 1:11 pm

James,
Thank you for the files, but it looks like problem does not relate to reports. HostMonitor generated more than 30,000 reports on our system (using your report profile) - no memory leakage.

May be there are leakage in some test method... could you send HML file with tests and all LST files?

BTW
Why you are using SP3?
Service Pack 4 for Windows 2000 fixes many errors, I think it fixes some resource leakage errors as well.
And if definitely fixes some security problems

Regards
Alex

sadek76 · Post by **sadek76** » Mon Apr 11, 2005 1:26 pm

Requested files are on the way. Can I restart the service now, or do you need anymore snapshots in its current state?

SP4 - I'll get it loaded ASATP.

KS-Soft · Post by **KS-Soft** » Mon Apr 11, 2005 2:09 pm

Yes, restart system. I don't see what other information I can get from screen shots

sadek76 · Post by **sadek76** » Wed Apr 13, 2005 3:25 pm

Looks like the UNC/Service tests might not be releasing system resources on 2003.
When I open a "cmd"window and run the "net use" command, I get pages of Disconnected and Connected mappings from my tests. I didn't use to see this in version 4.86, but did see it in other older versions.

I don't see this problem on 2000 server SP4 either.

KS-Soft · Post by **KS-Soft** » Wed Apr 13, 2005 10:08 pm

Problem that I have reproduced definitely releates to UNC test but.. its not really resource leakage problem. You are using "Connect as" option for each UNC test, so HostMonitor calls Windows API to establish network connection. Problem - Windows tries to establish connections ONE AFTER ANOTHER!! Its not multithreaded anymore!?

I have not seen such behavior before...
So, if there are network problem, Windows holds a lot of resources (for each connection) and releases them very slowly - about 30 sec for test item. You have about 1000 UNC tests, as a result system allocates too much resources and releases them within hours.

Another question how it works when Windows 2003 can establish connections.. unforunatelly we do not have 1000 systems. Probably it cannot hold so many connections either...

To be continued...

Regards
Alex

sadek76 · Post by **sadek76** » Thu Apr 14, 2005 9:56 am

I painfully chaged ALL of my UNC tests to use the "Connection Manager" and restarted my server.

Currently I see the tests processing normally and the net use command in the cmd window does not show any connections

KS-Soft · Post by **KS-Soft** » Thu Apr 14, 2005 10:09 am

Connection Manager uses the same Windows function, so I am not sure it can help

Lets hope...

Regards
Alex

sadek76 · Post by **sadek76** » Thu May 19, 2005 10:02 am

Was a fix for this ever released?

KS-Soft · Post by **KS-Soft** » Thu May 19, 2005 11:16 am

Fix for this problem?

Problem that I have reproduced definitely releates to UNC test but.. its not really resource leakage problem. You are using "Connect as" option for each UNC test, so HostMonitor calls Windows API to establish network connection. Problem - Windows tries to establish connections ONE AFTER ANOTHER!! Its not multithreaded anymore!? I have not seen such behavior before...
So, if there are network problem, Windows holds a lot of resources (for each connection) and releases them very slowly - about 30 sec for test item. You have about 1000 UNC tests, as a result system allocates too much resources and releases them within hours.

I am afraid we cannot fix that

Problem is inside Windows code...

But we found solution for another problem:

added new option for "Generate reports" action. "Use report pool" option tells HostMonitor that report generation can be deferred for 1-2 seconds. In some cases this option noticeably reduces resource usage, e.g. if you use "Generate reports" action for many test items that can change status at the same time. However you should not use this option if report must be processed immediately; e.g. you are using 2nd action to send reports by e-mail or you are using some script to publish report on your web site.

We did not find any resource leakage in Report Manager either, but sometimes resource usage can be very high. This option allows to reduce resource usage in many times.

Regards
Alex