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32 bit Eclipse: JRE and JDK versions needed

Apologies in advance. I know this is a basic question.
I am new to server administration. I am administering a server where the users do Java development.
They have a Java-based application and do development in Eclipse. Eclipse is 32-bit. The OS is 64-bit.
I recently updated the JDK and JRE on the server. I have both the 64-bit and 32-bit of each installed.
Eclipse ran into an error where it couldn't start after I had updated to the new JRE and JDK. So I took some advice online and updated the -vm path in the Eclipse .INI file to point to the new 32-bit JRE path. It now works.
I have two main questions:
Will updating the JRE and JDK EVER cause an issue with development, or as long as they can open up Eclipse and use at least one version of the JRE or JDK, they will be fine? I guess my fear is that they are going to develop in a certain version and the next version will cause issues down the line.
They develop in 32-bit Eclipse (not sure why they chose 32-bit) but their application runs with 64-bit Java (that is where the path points to for that installation). If something is developed in 32-bit Eclipse can it run with 64-bit Java? Side question: is there a certain advantage with developing with 32-bit Eclipse on a 64-bit system or is it personal choice?
Thanks a lot and cheers!

I guess my fear is that they are going to develop in a certain version and the next version will cause issues down the line.
Java 6 and 7 are end of life; Java 8 code should still be run when Java 9+ rolls out. I've not been aware of any backwards compatibility issues in recent years, it's only forward compatibility that doesn't work (running Java 8 compiled libraries with JRE 7).
They develop in 32-bit Eclipse (not sure why they chose 32-bit) but their application runs with 64-bit Java
The IDE and code run in separate processes. There's no harm in using the 64bit JDK with 32bit editor.
Eclipse 32 bits running on 64 bits JVM
Should I use Eclipse 32bits or 64bits on my new machine?

Will updating the JRE and JDK EVER cause an issue with development...
I believe it technically could render what you developed "obsolete" if you're initially using one JDK with some specs and change for another one with specs that are not "compatible" with what you built so far. By specs, I mean the libraries, tools, etc that the JDK contains. But I would say it would be unlikely that such problems occur. It personally never happened to me. I'd like to have someone with more knowledge give more details though and validate what I'm saying or correct me if I'm wrong.
If something is developed in 32-bit Eclipse can it run with 64-bit
Java?
To my knowledge, there are not related things. In my mind, Eclipse is just your IDE and it allows you to build/compile code using specific JDK (32 or 64 bits). As a matter of fact, you don't even need eclipse to build code but you definitely need a JDK: it's the JDK that give you the tools to compile code that "targets" a specific JRE/JVM and Eclipse is using the tools your JDK provide.
So yes, you can use eclipse 32 bits to build code for a 64 bits JRE.

Eclipse won't start with Xmx set to 1024m anymore, though there is enough memory

My Eclipse (or, more specific, Spring Tool Suite) version is:
Version: 3.6.3.RELEASE
Build Id: 201411281415
Platform: Eclipse Luna SR1 (4.4.1)
It worked fine, until recently, when I started getting the following error after opening Eclipse:
Error: Could not create the Java Virtual Machine
Error: A fatal exception occured. Program will exit.
My start options include -vm <path to javaw> -vmargs -Xmx1024m -XX:MaxPermSize=256m, I am using jdk1.7.0_79, the 32 bit version, on a 64bit Windows.
I discovered, when setting -Xmx to 768m, Eclipse will start most of the time. I also noticed that starting eclipse began to fail when I installed the MySQL service; if I deactivate it, the Task Manager shows me I have roughly 4gb of 16gb of RAM consumed; with MySQL running, that value increases to 5gb.
What is the reason, when there are 5gb consumed and roughly 11gb of RAM left, that no JDK can be created, and is there a known workaround?

It is likely because of lack of virtual address space. Remember that 32-bit processes have only 2GB of virtual space, which is needed for:
application code
DLLs, both application DLLs and shared DLLs like hooks
java off-heap needs: code caches, buffers, etc.
java heap itself
So, physical RAM is unrelated.
What likely happened?
Eclipse grew heavier so JVM needs more off-heap to function
What you can do?
Uninstall unneeded plugins, shut down your antivirus or other software that could intervene with Eclipse, use 64bit java. 64bit apps are faster on modern processors + 64-bit java uses compressedOps so it could make sense.

In the past i had simlar issues, but no solution. I reached the limit with -Xmx1500m.
See also Maximum Java heap size of a 32-bit JVM on a 64-bit OS.
Is using the 64 bit Version of the JDK no option?

Java VisualVM missing features

I have a Java application, and I'd like to monitor it using Java VisualVM (jvisualvm).
However, in the VisualVM window very little data can be seen. Also, I can't take a heap dump.
Here is a screenshot of what it looks like, with another test app I wrote:
I can monitor memory usage, classes loaded and threads. Heap dumps, performing GC as well as sampling is disabled.
I have tried adding -Dcom.sun.management.jxmremote to VM arguments, as described here. This is showing up in the Installation Details window. However, it does not appear in the Java process arguments. (should it?)
I also tried to click the button in my test app until an OutOfMemoryError occurred. No heap dump; that is not weird as Heap Dump on OOME is disabled.
What could I do to solve this?

I had this problem because I was running JVisualVM from a different JRE/JDK installation than the target process. It seems that the two must be coming from the same place or it grays out the Heap Dump button.

It seems there was a problem with different Java versions.
A long story short: If JDK is outdated re-install it, and delete Java executables from C:\Windows\System32 and C:\Windows\SysWOW64.
Firstly, I want to tell you that I have multiple versions of Java on my computer. My JDK is 32-bit because of some drivers not running with 64-bit Java. Also, I have both 32-bit and 64-bit JRE installed, the latter for better performance for Java games.
My JDK was version 7, update 40. The VisualVM was so also that version. However, my JRE with auto updates was version 7, update 45.
java -version told me it was version 45 (which it was), so I didn't think the problem was there.
Then, I checked the versions via Control Panel. I now knew my JDK was outdated, so I uninstalled it and redownloaded it.
Uninstalling removed Java from the system path, so jvisualvm wouldn't run. I added it to the path. Now both the app and VisualVM ran normally, but still the problem persisted.
The final problem was that the system was using the java.exe from C:\Windows\System32 instead of the JDK one. By the date it seemed to be the latest one, but maybe it was that the JRE was installed in a different location that the VisualVM (= the JDK).
Finally, I just deleted the Java executables in both C:\Windows\System32 and C:\Windows\SysWOW64.

Why isn't VisualVM showing all the normal tabs?

Usually I see all these tabs in VisualVM for locally running Java programs:
However, I have one local program which is currently only showing me Overview and Monitor (even though it usually shows all those shown above):
Also interesting is that VisualVM itself doesn't present the Profile tab:
All three of the programs shown are running with the same JVM with the same Java Home.
What controls which tabs are shown for a particular program? How can I get them all back for my program showing just Overview and Monitor?
I have Visual VM 1.3.5 (latest at this date) and JDK 1.7.0_17.

I found that this was the issue of usage of wrong JDK version. In my case my application was running on 64bit JDK and I started VisualVM from 32bit JDK.
After starting VisualVM from the same JDK on which my application is running, everything was fine. Hope it will help you.

You might need to enable jmx ports on your app. Try adding these switches to your VM and see if the tabs appear again:
-Dcom.sun.management.jmxremote.port=6789 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false

I've just removed ~/.visualvm and reran, See https://java.net/jira/browse/VISUALVM-598

As most of the people mentioned,
The issue was due to the version mismatch of virtualvm and your application.
additionally,
visualvm is bundled in oracle which supports jdk up to 9.
If you are using >9, please make sure you go for another profiler.

What worked for me was specifying the "Start profiling from" classes. If I left this blank, I didn't get the profiler tab. When I specified it, I did. I should probably note that this was a web application running under Tomcat, so I specified org.apache.catalina.startup.** as the starting class.

Check that proxy is disabled if you are running VisualVM for local application

I had a similar problem with missing profiler tab in VisualVM. I'm using Oracle JDK 1.8 and want to profile web application running on Tomcat 8 (JPA, Spring, Hibernate, Vaadin, etc).
I tried all above-mentioned solutions and many others found on the internet, but unfortunately, none of them solved missing profiler tab issue.
So I switched to Java Mission Control profiling tool (JMC + Flight Recorder) which is a part of standard Oracle JDK (from JDK 1.7 update 40) and it works great.

In my case, the issue was the usage of wrong JDK version. My App was running on jdk1.7.0_80, VisualVm running with jdk1.8.0_162.
Replacing the APP JDK version from 1.7.0_79 to 1.7.0_80 fixes the problem.

“Error occurred during initialization of VM; Could not reserve enough space for object heap” using -Xmx3G

First of all, I have a box with 8gb of ram, so I doubt total memory is the issue.
This application is running fine on machines with 6gb or less.
I am trying to reserve 3GB of space using -Xmx3G under "VM Arguments" in Run Configurations in Eclipse.
Every time I try to reserve more than 1500mb, I get this error:
“Error occurred during initialization of VM; Could not reserve enough space for object heap” using -Xmx3G
What is going on here?

Could it be that you're using a 32-bit jvm on that machine?

Here is how to fix it:
Go to Start->Control Panel->System->Advanced(tab)->Environment Variables->System
Variables->New:
Variable name: _JAVA_OPTIONS
Variable value: -Xmx512M
Variable name: Path
Variable value: ;C:\Program Files\Java\jre6\bin;F:\JDK\bin;
Change this to your appropriate path.

This is actually not an Eclipse-specific issue; it's a general
Java-on-Windows issue. It's because of how the JVM allocates memory on
Windows; it insists on allocating a contiguous chunk of memory, which
often Windows can't provide, even if there are enough separate chunks to
satisfy the allocation request.
There are utilities that will try to help Windows "defrag" its memory,
which would, in theory, help this situation; but I've not really tried
them in earnest so can't speak to their effectiveness.
One thing that I've heard sometimes that might help is to reboot Windows
and, before starting any other apps, launch the Java app that needs the
big chunk of memory. If you're lucky, Windows won't have fragmented its
memory space yet and Java will get the contiguous block that is asks for.
Somewhere out on the interwebs there are more technical explanations and
analyses of this issue, but I don't have any references handy.
I did find this, though, which looks helpful: https://stackoverflow.com/a/497757/639520

First the JRE of 32bits can't use more ~1.5Gb of ram. So if you want more, use a 64bits JRE.
Second, When a new JVM starts, this sum the -Xmx property of the all JVM that are running, and check if there is enough memory left on the system to run at their own -Xmx, if is not enough then the error occurs.

I was using Liferay with Tomcat server from eclipse IDE.
I was stuck with this same error on click on server start up.
Double click on server from eclipse.
it open up Server Overview page. Updated memory arguments from -Xmx1024m -XX:MaxPermSize=256m to -Xmx512m -XX:MaxPermSize=256m.
Then it was working for me.

Make sure that Eclipse is actually running the same JVM you think it's running. If you use java in your web browser ever, you likely have a 32-bit version floating around too that might be taking precedence if it installed or updated lately.
To be absolutely sure, I recommend adding these two lines to your eclipse.ini file at the top:
-vm
C:/Java/jdk1.6.0_27/bin
...where on my machine C:/Java/jdk1.6.0_27/bin where the JVM I know is 64-bit is located. Be sure to have the bin folder there.
(As a bonus, on Windows 7, this also allows you to actually "pin the tab" which is why I had to do this for my own usage)

This is the issue of Heap size. Edit your .bat (Batch file). It might be showing Heap size 1024. Change it to 512 Then it should work.

Just put # symbol in front of org.gradle.jvmargs=-Xmx1536m in gradle.properties
# org.gradle.jvmargs=-Xmx1536m

I also had the same problem while using Eclipse which was 32 bit and the JVM used by it was 64 bit.
When I routed the Eclipse to 32 bit JVM then it worked

I know that i am a bit late, but here my answer comes:
I just installed the Java online Version from Oracle(not the offline 64-Bit one).
After having added the JAVA_HOME ENV variable, it just worked!
Hope I could help :)

Probably you are trying wrong options anyways.
I got a similar error with supporting error log:
Java HotSpot(TM) Client VM warning: ignoring option PermSize=32M; support was removed in 8.0
Java HotSpot(TM) Client VM warning: ignoring option MaxPermSize=128M; support was removed in 8.0
Im my case, the software did not support java 8 yet(script was using old JVM arguments) but I had had java 8 by default.

One of the reason for this issue is no memory available for Tomcat to start. Try to delete the unwanted running software from windows and restart the eclipse and tomcat.

Solution is simple. No need to go deep into this issue.
If you are running on 64bit machine then follow below steps:
Unistall 32 bit java first (check in C:\Program Files (x86) for its existence)
Install the newer version JDK kit 64 bit (includes JRE)
Set the environment path (To avoid conflict error if you have two different 64bit JRE)
Check in command prompt by typing javac command.
Restart / Done
You can have two different Java installed but don't forgot to set path.

Please set JAVA_OPTS=-Xms256m -Xmx512m in environment variables, it should solve the issue, it worked for me.

Find out if you are using a 32bit version or 64bit version of Java. To know that use the command
java -version
The 3rd line of the output should give you if it 32bit or 64bit.
If it is 32bit uninstall and install a 64bit version.