We had 5 applications over a linode(Ubuntu 10.04 32 bit) of 1G RAM. Recently we moved one of the applications out of that linode to another of 512M. The application is built on Java EE and was working pretty stable on the old server. On the new server however tomcat(Version 6 on both servers) crashes every now and then without any logs. The only difference on the new server is that we are using nginx as the web server against apache2 on the old and the new server uses Ubuntu 12, 64 bit. There is no reason to doubt a memory leak because the application was behaving well on the old server. Are there any tomcat optmizations to be done to prevent such kind of crashes. I doubt if the reason is load due to traffic(since the new server has lower RAM) as well, because even in the middle of the night when there are just about 10 concurrent users, tomcat still crashes. Any insight towards the problem would be appreciated.
I checked the RAM usage and tomcat constantly occupies about 60% of the memory and all of a sudden crashes and goes to 0. I have used a bash script and run it as a cron job every 5 minutes on the new server to check if tomcat is down and restart it automatically. Could that be causing the issue? The script is mentioned below
if [ "$(/etc/init.d/tomcat6 status)" == " * Tomcat servlet engine is not running." ]; then /etc/init.d/tomcat6 start; fi
Please note, I am not an expert at server configuration. I can just about configure a server to install and get required things running.
You moved your app from a 32-bit Hotspot JVM to a 64-bit Openjdk JVM. And on the new server you have less RAM.
First I would try to install the same 32bit Hotspot JVM on the new server,and see if the crashes still occur. If they do, I would start adding more memory, and adjust xmx etc' accordingly.
I upgraded the RAM to 1GB, downgraded to Ubuntu 12, 32 Bit, reinstalled JVM 32 bit and now the server works like a charm. I was unable to zero down on the root cause, but the most possible cause should be either the 64bit OS or the 64 bit JVM eating too much memory. Thanks for your help.
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My setup is as follows:
Ubuntu 20.04 server (16GB RAM) which runs Docker and Elasticsearch 6.8.16 image in a container with following env values -e JAVA_OPTS="-Xmx2g -Xms1g -XX:MaxPermSize=1g".
It also hosts two apps on Tomcat 9, and I have also set up these envs for Tomcat via setenv.sh in Tomcat's bin folder.
However, after a few hours, my remaining memory is less than 100MB and it happens every day. It stabilizes after I reboot the server, but after a few hours it falls under 100MB again.
Does anyone know how can I fix this?
If anyone needs any additional information, I am more than happy to provide it.
P.S. For some reason, my CPU always has 100% usage on one core while the other one is below 10%.
Thanks in advance!
I got into a HTML/CSS/JavaScript course and I need Docker Desktop installed an functionally on my laptop. The problem is that I can not start it because I do not have enough memory, the error is appearing every time when I try to start it. I have tried to solve it by lowering the settings of the Docker Engine, free up some memory with RAMMap and turn Windows to performance mode, but unfortunately the error is still here.
The laptop that I work on has only 2 GB of RAM. Is there a solution to start Docker?
I have recently started using docker for new development work, however I am still required to switch back to working on our older on-premise offering from time to time. That is, I sometimes need to shutdown docker and spin up a an installation of our on premise server.
I find that when I do this with docker installed the performance of this server is terrible, essentially unusable, I need to uninstall docker to get it to work again.
When I have docker running I can see it using the memory (my machine has 32 GB of RAM, I am telling docker to use 16) and when I shutdown docker I can see it being released, according to the task manager anyway, and I can also see on hyper-v manager that the VM has been shutdown. However the performance of on-premise server install continues to act as the memory is in use. This is not a small performance hit, actions that should take 1 second take 20 or 30.
It would seem like docker is not actually releasing the memory on shutdown and only does so when I actually uninstall it, when I do this performance recovers completely.
Is this a known issue? Is there anything else I can try to see where the memory is going? I can find no other reports about it.
I am using windows 10 with docker version 17.03.1-ce-win5 (10743)
I'm just starting to learn Grails and Groovy. Did a fresh install of Grails 1.3.8 today and it crawls - I must have something in my environment causing a problem. I ran create-app (following a tutorial), then run-app. Both took quite a while but hey, first time thru. Ran run-app again, took almost 5 minutes, apparently int eh compiling phase. Windows 7 machine with 4 GB memory, Intel i5 CPU. Don't know where to start looking, but know this isn't normal.
When I've run into this normally I'm out of heap or permGen space. Fire up visualvm and check both of those memory limits. It'll slowdown considerably before crashing if your memory limits are too small
I wonder how it happens for you. I have 2gb ram and I run Ubuntu on pc and it's so fast. First check your memory limits.
And for your question, you can find a good disscussion over here.
Recently I configured my instance into a micro environment in EC2 with glassfish and mysql in windows..
I deployed my war and i was able to access my site through http.
I changed my application and redeployed the war and it also worked.
When I was about to redeploy the war for 4th or 5th time, the application got deployed, I saw the message in the log file. But I was unable to access the site through http.
Then I tried the command "asadmin list-applications" and I got the following message.
Error occurred during initialization of VM
Could not reserve enough space for object heap
After that I was not able to connect to my instance through RDP and I had to reboot, I was able to access it again after that. I started the servers again (glassfish mysql), but no luck.
I noticed that the memory usage is around 90% or more. CPU isage is low.
now I can not access my site through http. what shall i do ?
Thanks in advance !
Honestly, there are a couple issues working against you here:
1) Windows requires FAR more RAM than Ubuntu to run at a minimum decent level.
2) GlassFish has a much larger footprint than Tomcat or Jetty.
Is there any particular reason you need Windows? Like is there a specific need that your server run some executables for file processing or something like that outside the JVM? Most would agree that Linux (Ubuntu or other) will give you much better results in performance and stability to run an App Server like GlassFish in any environment.