Multiple JVm instances error in iplanet 4.1

the error message is :
info ( 1184): JVM instance has already been created within the process, numVMs=1
I have an NSAPI filter which uses JNI and will create an individual JavaVM.
I understand in the process no more than 1 JavaVM shall be initialized yet I can't find a way to attach my NSAPI filter to the JavaVM created by the iplanet server.
Does anybody has any idea how to solve this?

Thanks for your reply. It seems odd though that IWS 4.1 seems to work fine w/sdk1.4.1 on my WinNT machine???

Similar Messages

Multiple JVM instances

Dear all,
I am trying to create multiple JVM instances using createJavaVM(...) but I can't do it. When I try to create the second instance, the function returns an error.
Does anybody know about getting multiple JVM instances running??
Thanks in advance,

Hallo,
createJavaVM(...) trys to create a JVM in your current
process, so I am not surprised that you get an error
the second time round, because there is already a JVM
in the process. If you want multiple JVMs, each needs
to be in its own process.
Why do you want to create more than one JVM in your
process? The JVM is multithreadable, and you can start
more than one thread in the JVM. Would that do what
you want?I need multiple instances because my application needs nearly 2Gb of memory and the maximum heap I get is 1700 Mb. I think with multiple instances, I'll get it.
Do you know about getting a bigger heap??
>
David Singleton
[email protected]

Multiple JVM instances and host computer performance

Hi,
I was wondering if anyone has any facts or sources about how running multiple JVM instances impacts the performance of the hosting computer ?
For example, say you have a long running server process that creates a JVM, how is the performance of the computer impacted if there are five of those processes running, versus ten versus ...
This is a very "it depends" question, but I would like to get an idea of the baseline performance impact that comes with running a JVM, and if there is anyone here that has experience running multiple JVMs I'd appreciate any feedback, whether it's "don't do it, ever" or "no problem!"
Thanks

My only experience with multiple VMs is when I have several Java GUI apps (eclipse, jedit, dbvisualizer) plus tomcat and maybe an ant running on XP.
I don't think that the existence of multiple VMs is in and of itself a problems, but JVMs do tend to be fairly memory hungry, so if you don't have a lot of RAM, you may find yourself crawling along as swapping heats up.
I think that later versions of the Windows VM have started to take advantage of sharing certain core libraries, or pieces of them, so that you don't have as big an incremental memory footprint for additional VMs. I don't know which versions or how much this actually reduces the foot print of second and subsequent VMs though.

Multiple jvm/instances/auto restart

Hi
I have two mid tiers and both are load balanced by BigIP load balancer .
I want to know the following
1. How can I increase the jvm process and what is it's advantages/disadvantages ?
2. Is it possible to set automatic restart feature in the Application server ?
3. In some article I found that we can create multiple oc4j instance and give the same
context root . What is the advantages/disadvantages ?
4. Is there any feature in the app sever for monitoring like if the appserver uses more resources or crashes we can send email to the administrator ?
Thanks,
Suneesh

Hello,
My answer is based on the fact that you are using OracleAS 10g (R1, 2 or 3) -which one are you using?-
OPMN: Oracle Process Management and Notification is the service in charge of starting and monitor the status of a process such as OC4J and its related JVM. Take a look to the OPMN documentation of your release. (and Administration Guide)
To have multiple OC4J that use the same context root (same application deployed) you need to have an instance with cluster enabled for several process of the same instance. Take a look to the deployment and configuration guide of your App server version.
OPMN, Clustering, and Oracle Deployment guides will answer the 4 questions you have.
Regards
Tugdual Grall

Multiple JVM instances stop simultaneously.

We have a customer running JRE 1.5.0_8 on a Windows 2003 Server.
We have multiple java applications running in the background on this server. We keep having an intermittent problem where all of these java applications shutdown at the same time (I'm talking within the same second). It apparently is somewhat of a clean shutdown because our shutdown hooks are running; however, these programs should not be stopping. There are no dumps being created by the JVM. It happened twice yesterday, but the day before did not happen at all.
These applications are spawned into the background by a windows service we wrote and this same service will restart the application automatically when they stop in this fashion so the customer really has not noticed. Sometimes when the applications are restarted, they will stop immediately and our service will start them again and they stay running.
We have logs running on these applications and there is nothing in these logs that would suggest the applications should shutdown.
These same applications are used at other customers' sites and we do not have this problem. This is; however, the only site running 1.5.0_8, all of the others are running previous versions of the JRE.
I do not know what kind of Windows patches has been installed by the client.

ping

Multiple JVMs foe One WL6.1 instance

Hi,
Is it possible to attach multiple JVMs to an instance of WLS6.1
so that all JVMs will be self sufficient in serving client requests....
If it is possible then any pointers in that direction..???
regards
aseem

Each WL server runs in one JVM. If you want to have 4 JVMs, then run 4 WL
servers in one cluster.
"Aseem Rastogi" <[email protected]> wrote in message
news:[email protected]..
currently our App runs on 2 Iplanet App Server ( they are in Cluster)
and each App server has 2 VMs so we we are getting the feel of 4independent
App Servers but Physically we are able to get away with only 2 boxes.
We want to achive the same thing in Weblogic...
thanx
aseem
Michael Reiche wrote:
1) What is your requirement?
2) Clustering.
"Aseem Rastogi" <[email protected]> wrote in message
news:[email protected]..
Hi,
Is it possible to attach multiple JVMs to an instance of WLS6.1
so that all JVMs will be self sufficient in serving client
requests....
>>>
If it is possible then any pointers in that direction..???
regards
aseem

Running Multiple JVM's on same Server has OutOfMemory - PermGen Errors

I have a scenario where I have 2 application servers. One is running one JVM and the other is running multiple JVMs.
Both are configured with:
-XX:+UseConcMarkSweepGC
-XX:+UseParNewGC
-XX:MaxPermSize=256m
-XX:+CMSPermGenSweepingEnabled
-XX:+CMSClassUnloadingEnabled
The server that is running with only 1 JVM runs stable, however the server that is running multiple JVMs has frequent crashes due to OutOfMemory - PermGen errors. The only other difference is the Heap size. 512mb for each JVM on the app server with multiple instances and 1GB for the server with 1 instance. Is there a relationship/settings that need to be tuned when running multiple JVM's on the same server to avoid this?
Thx

The only other difference is the Heap size. 512mb for each JVM on the app server with multiple instances and 1GB for the server with 1 instance.This isn't a trivial difference. Basically you're saying "When I give the server 1 GB then it's okay but when I give it 512 MB it's not okay." If I saw those symptoms I would take them at face value to start with.
So, turn off one of those servers on the machine that has two. Don't change anything else. Testable prediction: That won't fix your problem.

Load balancing HTTP requests for an OC4J instance w/multiple JVMs

Hello everyone,
I am using OAS 10.1.3.1 and wish to load balance HTTP requests across an OC4J group of one or more OC4J instances, where each like named OC4J instance may have multiple JVMs or it may just have one JVM.
My mod_oc4j.conf file would contain the following directives :
Oc4jSelectMethod roundrobin:local
Oc4jRoutingMode Static
Oc4JMount /xyz/* xyz
In the degenerate case, I would like to have an OC4J group with a cluster size of one, and have that one OC4J instance have two or more JVMs. I would like to be able to receive a request within my web application, determine that the JVM that has been sent the request is the wrong JVM to process the request, and then call HttpServletResponse.sendRedirect("/xyz"). Then, when the browser receives the HTTP 302 response and issues the subsequent HTTP request, have that request sent to a different JVM than the previous JVM that issued the sendRedirect().
What I have seen is that the subsequent request is sent back to the same JVM that issued the sendRedirect(). I also call invalidate() against the HttpSession prior to calling sendRedirect(), but that does not seem to affect the behavior that I see.
In the full blown case, I would have an OC4J group with a cluster size > 1, and each of those OC4J instances would have at least one JVM. In that case, I wish the sendRedirect() call to allow the subsequent request to be sent to any one of the OC4J instances in the group, and any one of those JVMs within all of those OC4J instances.
Can anyone verify that my mod_oc4j mount directive is appropriate given the select method and routing mode? What else might I need to do to have a chance to have a different JVM respond to the request that results from a sendRedirect()?
Thank you,
Doug

I should clarify that in the full blown environment, the OC4J instances that form a group will each be housed within a separate OAS instance that resides on its own machine.
So ideally, a request could be inbound to say OAS instance 1 on machine A, OC4J instance AA, JVM 2, and I need to force a redirect so that the request can actually be serviced by OAS instance 3 on machine C, OC4J instance AA, JVM 1, and I need to be able to call sendRedirect() against an HttpServletResponse from within a JVM until the subsequent request from the browser, Internet Explorer in my case, is serviced by that JVM.
Thanks,
Doug

Sync: Multiple Instance Error Causes Desktop Manager to Fail

I can no longer sync my Outloook calendar with my Bold 9650 using Desktop Manager 6 (bundle 3084). I failed multiple times, rebooted each device and tried again but still receive the same error. Error is a message from Windows that Desktop Manager has stopped working. The last few entries in the log indicate:
08:55:35.962 Sync information for application 'Calendar' in translator 'Outlook' --
08:55:35.962 Number of newly added records since last sync (New): 482
08:55:35.962 Number of records modified since last sync (Modified): 0
08:55:35.962 Number of records deleted since last sync (Deleted): 0
08:55:35.965 Performing two-way sync
08:55:35.966 ERROR: Multiple instance error. Remove a recurring instance or exception on (11/8/2011).
08:55:35.966 ERROR: Multiple instance error. Remove a recurring instance or exception "Bi-weekly Leadership Team Call".
I saw an entry in the Outlook calendar related to the error, but not in the BB calendar, and deleted it but this did not resolve the problem. At this point, I cannot get DM to complete synchronization. Has anyone else experienced this and identified a resolution?
thanks,
eric

Hi Eric,
Did you manage to resolve this? I have the same error and cannot get DM to complete the sync.
Thanks,
Johann

Ensuring one singleton instance for multiple JVMs

i am creating a singleton object. But singleton is per JVM (or rather per classloader) right? But i want to ensure only one instance of my singleton even if there are multiple jvms....how can i achieve that?

javanewbie80 wrote:
i am creating a singleton object. But singleton is per JVM (or rather per classloader) right? But i want to ensure only one instance of my singleton even if there are multiple jvms....how can i achieve that?You can't.
Given computers A and B. Neither have any connectivity by any means to the other.
Install the application on both and run it. There is no way for either application to know about the other thus only one of the following is possible.
1. Both applications run and create an instance. Then there are two instances and thus it fails.
2 The application refuses to run. Then there are none and thus it fails
Other solutions are possible given that some reasonable requirements based on actual business driven needs are presented.

How Can I Use Multiple Weblogic Instances in a Single OS

Hello Everyone,
Actually I have to install Some different applications. Few of them need weblogic 10.3.6 and others need 10.3.4. The OS am using is Oracle Enterprise Linux 5.
Now I am able to install 2 separate(One of 10.3.4 and 10.3.6) instances with two different users,In two different directories.
I have installed the weblogic 10.3.6 version with a user webadmin and installed node manager with port 5556. This is working fine.
The main problem here is :
In the second instance (10.3.4 ) installed with a a different user and gave the port number to NodeManager as 1600 and its not getting started. Its throwing error and also after some errors in the terminal am able to see that its reverting to port number 5556 only.
What might be the issue?
I have to install 2 different versions of weblogic in a single Server. But am failing with NodeManager. What Can I do to have multiple weblogic instances with multiple versions in a single server ?
Can anyone suggest a resolution for this please ?
Thanks in advance.

Pl do not spam these forums with multiple posts - How Can I Use Multiple Weblogic Instances in a Single OS

Need to get data from multiple database instances in a single query

Hi,
I need a small favour from you guys. The prob is as follows:
I need to get name, row_id from table A from schema 1 and gbu_name, name from table B from schema 2 where a.name = b.name. I wrote the query in the following manner:
SELECT a.name, a.row_id, b.gbu_name
FROM Schema1.A as a, Schema2.B as b
Where a.name = b.name
But this query is not working and the error is like " The table does not exists".
Please update me how to avoid the error and get the right sort of result.
Thanks & Regards,
Debabrata

Ah, youre actually asking different things.
In your topic title, you say youre running separate instances
In your body text, you say you are under different user/schema
So tell me, do you have more than one database or not? How many entries in your TNS file?
I would say, for "multiple database instances"
SELECT
a.id, b.id
FROM
tableA a
INNER JOIN
tableB@OTHER_DATABASE_LINK_NAME b <--NOTE!
USING(id)And of course you will have to look up CREATE PUBLIC DATABASE LINK sql..
Message was edited by:
charred

Multiple JVMs within app server - refresh of metdata not working

Hi guys.
We have an interesting scenario at present when running our application within a new test environment.
Our web-based application has the facility to refresh it's application metadata. This should mean that the next time the browser refreshes (or a user logs in to the application), the application will display based upon the refreshed metadata structure.
Previously, we have run our application on an app server with a single JVM without any dramas. ie. the refresh has always been reflected appropriately when viewing the application - as mentioned above.
However, we have installed the application in a new environment where the refreshing of meta data does not work consistently. That is, only about 50% of the time does the data refresh correctly. This can be seen by pressing the refresh button in an IE browser, so that the refreshed data appears approx. every second time the button is pressed. The only notable difference with this environment is that it runs 2 JVMs within the app server.
It seems that in this case, the 'old' data remains cached for the 'other' JVM, and that when the browser receives 'refreshed' data from the server, it does not always source from the same JVM.
This situation can be resolved by restarting the OC4J container, but this is not a desireable solution.
Is anyone aware of an OC4J parameter that can be set so that the 2 JVMs can run in synch so that both are refreshed appropriately when our meta data is cleared (refreshed) ? I don't believe this can be controlled within the Java source code, but I'm receptive to any other alternate solutions.
Thanks in advance.
Steve.

I'd like to embed multiple instances of the JVM within
a single, multi-threaded native server process. I'm
aware this was not possible with the Sun JDK in the
past.
Is this still true (for JDK 1.4.1 say)?Yes, this is still true.
If it's still not possible, are there any timetables
as of when it might be available? No.
Likelihood?Check the current list of JSRs at http://www.jcp.org.
Ah, btw: Is support for VM unloading (during
DestroyJavaVM()) available now?No.
>
In any case: does anybody know of a JVM
implementation
available for Linux which supports multiple VM
instances within a single process?Why do you need multiple VMs? Would multiple separate 'processes' within a single VM work? If so, have a look at:
http://www.cs.utah.edu/flux/janos/janosvm.html
http://www.javagroup.org/echidna/
Jim S.

Server, Multiple JVMs sources

Hi,
i've to create a (web serivce) server application. This application should be ready for clustering or something, if one server isn't fast enough.
I know already some things abou concurrency in Java. I'm no Java newbie. But i don't know how clustering works.
Does it depend on the used JVM?
Or is this for every server (i.e. Tomcat, JBOSS, ...) different?
What are the requirements in the webservice-layer and in the persistance layer?
Any good internet pages/PDFs which discusses this?
Any good books?
I really hope some can help me here, because it's very important for me.
Cheers,
Ingo

I just re-read the guidelines for a clustered web app over the weekend, so I think I've got things straight. Your application will have to be sensitive to two important issues:
1) A class which was previously a singleton may now be instantiated in multiple JVMs. The most obvious side effect of this is that the init() method of any servlet will have a different ServletConfig object passed to it for each JVM it is initialized in. As a result, the application context is no longer a valid place to store information, since the change to the application context is not necessarily propagated to the other JVMs. However, context-params will still be available from all JVMs. Another noticable side-effect is that static variables no longer work as expected (since there may be multiple instances of the same class).
2) The HttpSession object for a given session can only be in existence on one JVM at a time. If the HttpSession needs to migrate to another JVM, then it will be serialized and sent to the other JVM. As a result, adding an object to a session that is not Serializable may result in IllegalArgumentException being thrown. I'm guessing that in the case of a fail-over (node dies unexepectedly) that the HttpSession object is lost.
Brian

Multiple JVM's in one JDK

Hi,
I am curious to know if one JDK spawning multiple JVM's cause any memory/performance issues. The reason being, my company is planning to have number of applications running in one Weblogic Server instance with Multiple JVM's spawning out of same JDK.
Please let me know if this is possible and if there are any negative effects of following this approach.
Any help is greatly Appreciated.
Thanks

JDK installation is a just binary. There is not limit on creating number of JVM runtime process.
There should not be negative effect assuming you have enough capacity on hardware box.

Multiple JVm instances error in iplanet 4.1

Similar Messages

Maybe you are looking for