we are running Jboss 4.2.3 on Amazon AWS machine with 8 cores (CPUs)
under load we see that there is a single thread taking massive load on just one CPU, while the other are almost idle. (other threads are distributed on all CPUs)
we see it using top.
we are using an AJP connector, connected to an httpd instance.
could it be the AJP connector thread? or anything else? some sort of threads manager thread?
any info will be appreciated.
You should probably also post the OS and JVM information. The problem might be that your JVM is not using all the other CPU's because it's probably not optimized for multi-core/cpu architecture. JBoss 4.x is definitely not optimized for it but JBoss AS 7 is designed to leverage the multi-core architecture.
Related
i am testing out jboss eap 7.1 using adoptopenjdk 8 with openj9 (previously was using hotspot). i used visualvm to monitor it via jmx, and noticed that the reported cpu usage is consistently close to 100% (see attachment). when i used htop on the host, i found that the cpu usage is nowhere that figure. after switching back to hotspot, the reported cpu usage accurately reflects whatever was reported with htop again. however, if i use jconsole + openj9, the reported cpu usage is accurate as well.
does anyone know whether this inaccuracy is commonplace for openj9 + visualvm monitoring? thanks!
I managed to reproduce this with a trivial application (that just prints the time once a second). It appears something is broken in OpenJ9: I created an issue to track fixing it.
We are using Wildfly 10 and we want to use Red Hat AMQ 7 (standalone) remotely. I checked few documentation and found that ActiveMQ Artemis is also inbuilt in Wildfly 10, and I also configured it successfully to send and receive messages.
But as per our requirement, we want to use a remote AMQ broker so that it can be used as a centralized server and will be best suited in our enterprise requirement. Even I also want to understand the exact difference in using the ActiveMQ Artemis embedded in Wildfly and a remote Red Hat AMQ 7 instance, but I could not find enough information about it. If anyone is having any idea about it, please explain it.
I think there are three approaches to implement remote Red Hat AMQ.
Use the embedded ActiveMQ Artemis as a standalone server. I mean if we will install this Wildfly 10 in a separate server and if we can use that only for integration purpose and use the embedded ActiveMQ Artemis to connect with our Java application running on separate servers.
Install Red Hat AMQ 7.x as separate broker and connect it from the java application deployed on Wildfly 10. I checked Red Hat documentation and one point bothered me about this implementation as Red Hat claims "Currently AMQ 7.2 is only supported as a stand-alone broker. It has not be certified with EAP 7.0 or earlier. It is planned to be tested both as the internal broker of EAP 7.1 and as an external broker with EAP.". This is my preferred approach but I am not getting any documentation to implement it even Red Hat also not did it yet.
Install Apache ActiveMQ Artemis 2.x and integrate it from the application deployed in Wildfly 10.
I tried to get this information but as of now there is not much information available on internet for Artemis. It will be a great help if someone can explain the differences with pros and cons in above approaches.
Regard's
Ram
As much as I've looked, I can't find the hardware requirements for running minishift. Nothing mentioned in the Container Development Kit documentation, and the OpenShift documentation only mentions hardware requirements for production deployments.
I've been following RedHat's advice on running their Container Development Kit with nested KVM.
https://developers.redhat.com/blog/2018/02/13/red-hat-cdk-nested-kvm/
I may be pushing the limits. On a MacBook Air with 4x1.7GHz & 8GB RAM I’m running Fedora 27. Gave 6GB RAM & 2 cores to the RHEL Server and starting Minishift saw that it was giving 2 cores and 4GB RAM to VM. It took about 30 minutes to download and extract the 4 docker images. Things got progressively worse from there.
I’m trialing OpenShift Online. Would I run into a world of pain using Minishift directly on Fedora?
You would be better of running Minishift directly on Fedora 27 with KVM. Personally I use Minishift on Fedora 27. Using nested virtualisation will not give optimum performance as Minishift creates another VM to provision the OpenShift. So I will not recommend using nested virtualisation for Minishift. With the default settings i.e. 4GB RAM, 2 cores and 20GB disk you should be able to run few simple micro services on it. The resource requirement comes from the application you are trying to run on top of it. So if you are running an application which needs a lot of resources then you need to increase the resources to Minishift.
Once you know how much resources are fine for your application, you should save your configurations using "minishift config set" command. It will persist the settings across start/delete.
What are the optimal performance tuning settings to put in my sts.ini file to ensure STS runs well on my Mac?
I am looking to optimize two machines. One is a MacBook Pro with 16GB ram and a 6-core 2.6Gh i7 processor and the other is an 8GB dual-core processor 2.2Ghz.
I am looking to get a faster overall speed for STS. The thing that really slows me down is the change event handler process. When it starts running then everything slows down.
There are quite a few one-off guides around for optimal performance tuning of the Spring Tool Suite. Some are written for a Windows platform and some for an OS X platform. Since STS runs on the JVM I thought the optimal settings would work in either environment.
I haven't seen a well-done list of performance tuning options. It would be nice to see if the configuration should change based off of system properties such as RAM, processor, and number of cores.
I am running some experiments with memcached on Linux (x86-64). I am generating queries to the memcached server using memslap utility. I notice that memcached spends most of time is spent on system (i.e, OS functions). I was wondering if anybody has some insights about which functionality of OS is used heavily by memcached and thus spends most of its time on it.
Thanks
Arka
Memcached only major OS function, outside of daemon process, is related to the libevent. I believe memcached & libmemcached is compiled with OS's shared libevent library, and that time will be generalized as an OS function.