Palestra apresentada no TDC Floripa 2017

1. JAVA EM CONTAINERS DOCKER
PARAÍSO OU ESQUECIMENTO?
RICARDO MARTINELLI DE OLIVEIRA
Senior Software Engineer

2. DOCKER
KERNEL
NAMESPACES
CGROUPS
UNIONFS LIBCONTAINER
https://docs.docker.com/engine/docker-overview/#the-underlying-technology

3. https://docs.docker.com/engine/docker-overview/#docker-architecture

4. DOCKER
KERNEL
NAMESPACES
CGROUPS
UNIONFS LIBCONTAINER

5. CGROUPS
"CONTROL GROUPS PROVIDE A MECHANISM FOR
AGGREGATING/PARTITIONING SETS OF TASKS, AND ALL THEIR FUTURE
CHILDREN, INTO HIERARCHICAL GROUPS WITH SPECIALIZED BEHAVIOUR."
https://www.kernel.org/doc/Documentation/cgroup-v1/cgroups.txt

6. TOP CPUSET
CPUSET 1 CPUSET 2
(PROFESSORS) (STUDENTS)
Memory : Professors (50%), Students (30%), system (20%)
Disk : Professors (50%), Students (30%), system (20%)
Network : WWW browsing (20%), Network File System (60%), others (20%)
/
Professors (15%) students (5%)

7. # ECHO BROWSER_PID >
/SYS/FS/CGROUP/<RESTYPE>/<USERCLA
SS>/TASKS

8. E O JAVA?

9. https://docs.oracle.com/javase/8/docs/technotes/guides/vm/gctuning/ergonomics.html
JVM ERGONOMICS
"Ergonomics is the process by which the Java Virtual Machine (JVM) and garbage
collection tuning, such as behavior-based tuning, improve application performance. The
JVM provides platform-dependent default selections for the garbage collector, heap size,
and runtime compiler. These selections match the needs of different types of applications
while requiring less command-line tuning. In addition, behavior-based tuning dynamically
tunes the sizes of the heap to meet a specified behavior of the application."

10. PROBLEMAS

11. PROBLEMAS

12. JAVA 9 + CGROUPS
HTTP://HG.OPENJDK.JAVA.NET/JDK9/JDK9/HOTSPOT/REV/5F1D1DF0EA49

13. REFERÊNCIAS
https://developers.redhat.com/blog/2017/03/14/java-inside-docker/
https://docs.openshift.com/container-platform/3.5/creating_images/guidelines.html
https://goldmann.pl/blog/2014/09/11/resource-management-in-docker/
https://docs.docker.com/engine/admin/runmetrics/
https://fabiokung.com/2014/03/13/memory-inside-linux-containers/
http://trustmeiamadeveloper.com/2016/03/18/where-is-my-memory-java/
https://engineering.linkedin.com/blog/2016/08/don_t-let-linux-control-groups-uncontrolled
https://engineering.linkedin.com/blog/2016/11/application-pauses-when-running-jvm-inside-linux-
control-groups

14. OBRIGADO!
@rimolive
https://github.com/rimolive