Re: Mesos , Java & hardware isolation

[deadbrain]

Thanks for this detail Justin I just checked on mercurial and you are 
right , we used a jdk 8u151 and I have seen a couple of cgroups fixes in 
the u152

Thanks again

Regards


On 11/07/2017 05:06 PM, Justin Lee wrote:
It may also depend on the version of Java you're using - depending on 
the version of Java that you're using, they may or may not properly 
pick up the cgroup settings vs. the total number of cores available.

I don't know which version(s) of Java work, but I think the later 
versions have better support.

Thanks,
Justin Lee

On Tue, Nov 7, 2017 at 10:18 AM, deadbrain <jerome.moli...@gmail.com 
<mailto:jerome.moli...@gmail.com>> wrote:

    Thanks Thodoris for you help I will need to check with people
    managing the infrastructure to see what parameters are passed to
    our agents...

    Thanks again for the tips

    Regards



    On 11/07/2017 04:10 PM, Thodoris Zois wrote:

        Hello,

        I don't really know if i can help you but i used Docker
        containers in Mesos with isolation and everything was perfect.
        So are you using Mesos containerizer? Did you enable
        cgroups/mem, cgroups/cpu on each agent? As it concerns CPU,
        cgroups do not limit the anount of CPU if its the only running
        application. In order to limit exactly CPU you need to enable
        cfs on each agent.

        Thodoris

            On 7 Nov 2017, at 15:28, deadbrain
            <jerome.moli...@gmail.com
            <mailto:jerome.moli...@gmail.com>> wrote:

            Hi all,

            I expect to be at the right place for my question...

            We are hosting Java micro services exposed as docker
            containers (Spring Boot applications inside) inside Mesos....

            We face 2 major problems:

            - hardware isolation (number of cores seen by Java Virtual
            Machines) makes our applications go crazy because JVM sees
            all cores and not the only ones given in the Mesos config
            parameters as a consequence GC heuristics are wrong and 
            some config values in some libraries are false too
            (Undertow web server spawns 8*number of cores as workers
            thread pool)...

            In Linux since the 2.4.19 kernel we have the per process
            namespace option to limit the hardware vision of any
            container... What would  be the solution on Mesos ?


            - CPU starvation : some micro services do not seem to have
            the required CPU time to work, what kind of advices could
            you give me to have a better understanding regarding this
            problem....

            Statement: we can see very long partial GC times (about 4
            seconds) , standard times would be about 50ms....


            Thanks for your help

            Kind regards

            Jerome