JBoss WildFly 15.0.1 Final not starting on ubuntu 14.04 vServer with 2 GB: insufficient memory for JRE

Question

I am trying to get JBoss WildFly 15.0.1 Final to start on a rather small ubuntu 14.04 vServer. The server has only 2 GB of RAM.

I tried to start WildFly many times without success. The JVM seems to require a lot more RAM than I had ever expected.

Here's the console output:

root@t2g55:~# service wildfly start
 * Starting WildFly Application Server wildfly
 * WildFly Application Server failed to start within the timeout allowed.



root@t2g55:~# cat /var/log/wildfly/console.log
=========================================================================

  JBoss Bootstrap Environment

  JBOSS_HOME: /opt/wildfly

  JAVA: /usr/bin/java

  JAVA_OPTS:  -server -Xms768m -Xmx1536m -XX:MetaspaceSize=96M -XX:MaxMetaspaceSize=256m -Djava.net.preferIPv4Stack=true -Djboss.modules.system.pkgs=org.jboss.byteman -Djava.awt.headless=true

=========================================================================

OpenJDK 64-Bit Server VM warning: INFO: os::commit_memory(0x00000000a0000000, 536870912, 0) failed; error='Cannot allocate memory' (errno=12)
#
# There is insufficient memory for the Java Runtime Environment to continue.
# Native memory allocation (mmap) failed to map 536870912 bytes for committing reserved memory.
# An error report file with more information is saved as:
# /opt/wildfly-15.0.1.Final/hs_err_pid1379.log
1379


root@t2g55:~# free
             total       used       free     shared    buffers     cached
Mem:       2097152     258748    1838404         64          0      38644
-/+ buffers/cache:     220104    1877048
Swap:      2097152          0    2097152


root@t2g55:~# java -version
openjdk version "1.8.0_222"
OpenJDK Runtime Environment (build 1.8.0_222-8u222-b10-1~14.04-b10)
OpenJDK 64-Bit Server VM (build 25.222-b10, mixed mode)


root@t2g55:~#

As you can see I specified JAVA_OPTS: -server -Xms768m -Xmx1536m ..., which I thought should suffice for a WildFly server to start. Please not, that the standalone.xml has a datasource defined to a MySQL DB.

Here's the start of the dump .log:

root@t2g55:~# cat /opt/wildfly-15.0.1.Final/hs_err_pid1379.log
#
# There is insufficient memory for the Java Runtime Environment to continue.
# Native memory allocation (mmap) failed to map 536870912 bytes for committing reserved memory.
# Possible reasons:
#   The system is out of physical RAM or swap space
#   The process is running with CompressedOops enabled, and the Java Heap may be blocking the growth of the native heap
# Possible solutions:
#   Reduce memory load on the system
#   Increase physical memory or swap space
#   Check if swap backing store is full
#   Decrease Java heap size (-Xmx/-Xms)
#   Decrease number of Java threads
#   Decrease Java thread stack sizes (-Xss)
#   Set larger code cache with -XX:ReservedCodeCacheSize=
# This output file may be truncated or incomplete.
#
#  Out of Memory Error (os_linux.cpp:2757), pid=1379, tid=0x00007f62486c6700
#
# JRE version:  (8.0_222-b10) (build )
# Java VM: OpenJDK 64-Bit Server VM (25.222-b10 mixed mode linux-amd64 compressed oops)
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#

---------------  T H R E A D  ---------------
.
.
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QUESTION:

Can this be solved with this amount of memory or do I simply have too few RAM? What else could I probably try?

I don't really want my provider to go up with the mem successively only to find there's some other problem with Java, the JVM or anything...

Thanks

EDIT 1:

The vServer provider uses OpenVZ for its virtualization.

Info: they just pushed my to 4GB, then once, I got JBoss up and running. After reboot WildFly again refuses to start: same thing, not enough memory (even though I switch between Java 8 and Java 11 runtimes).

CMD to start JBoss WildFly: sh /opt/wildfly/bin/standalone.sh &, standalone.xml appears to be OK. I removed the ExampleDS, three entries commented.

Answer 1

It was indeed a server virtualization issue with OpenVZ.

Quote (in German):

Hi, das Problem nach bei den user_beancounters, genauer gesagt bei privvmpages, diese waren > zu gering eingestellt. https://wiki.openvz.org/UBC_secondary_parameters#privvmpages

Mit freundlichen Grüßen

Mr X

Translation:

Hi, the problem was with the user_beancounters, that is with the privvmpages, these were set too low. https://wiki.openvz.org/UBC_secondary_parameters#privvmpages

Best regards

Mr X

I don't know exactly what he did in detail, but that resolved it.

I now run on a 2GB machine without any problems and memory usage of mysqld + standalone.sh (WildFly + webapp) is around 800 MB.