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From הילה <>
Subject Re: [OT] Memory Leak in Tomcat
Date Thu, 24 Feb 2011 08:09:37 GMT
I'll try to check what you suggested. sounds like something that maybe shed
some light on this issue.
Thanks :]

2011/2/23 André Warnier <>

> הילה wrote:
>> Yes, I've read you other mail about the Jprofiler. I've run the Jprofiler
>> for a weak until it generated a stuck process on the DB and crashed the
>> application (even though it ran on the app server, and not the DB server)
>> I'm not too familiar with Tomcat tweaks and java monitoring, so i'll try
>> to
>> go over your mail again and see if I can extract from it something that I
>> can work with :]
>>  I hate to barge in (again?) in what is starting to look like a nice
> slinging match, but I think that we have already pretty much established
> that the memory leak, if any, happens in the jDTS (?) driver and/or the
> ntlmauth.dll that it is using, and not in Tomcat code.
> If it is in the ntlmauth.dll, I doubt that any Java tool will show
> anything.
> הילה, how exactly are you seeing that the Tomcat process is leaking memory
> ?
> With the MS Task Manager ?
> And, where exactly does that ntlmauth.dll come from ?
> @Chris :
> Apparently, the database being used accepts either plain text
> authentication, or NTLM authentication.
> And apparently also, the setup is such that in either case, the login to
> the database is done using a single user-id, provided "by Tomcat".
> One can discuss if this is, in the general scheme of things, an appropriate
> way in terms of security of access to the data in the database.
> But in the case of plain text authentication, the user-id and password used
> are stored in a Tomcat configuration file, in plain text.
> In the case of the NTLM authentication, the user-id under which tomcat runs
> can be easily discovered, but the password cannot.
> So I would think that in that limited sense, using NTLM offers an
> improvement.
> Now of course if at the same time, a bug in the jDTS driver or the
> ntlmauth.dll causes the Tomcat process to need more and more memory over
> time, the advantage is less evident.
> To nevertheless make some progress at identifying the culprit, I suggest
> the following procedure :
> Leave the user-id under which Tomcat itself is running as it is, using the
> Windows Domain user.  Also leave the database as it is.
> But change back the authentication used for the database, to the plain-text
> setting.
> This way, the jDTS driver will still be there, but it will no longer be
> using the additional dll, and will authenticate to the DB with the
> plain-text user-id and password.
> Then check if the Tomcat process is still leaking memory.
> If it is not, then you know for sure that the leak is in ntlmauth.dll (or
> in the jDTS driver, but only when it using NTLM authentication).
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