Cannot start elasticsearch in alpine

Hi,
I create and alpine vm with virtual box on windows and I am trying to deploy docker with elasticsearch in alpine.
When I try to start container I receive:

elasticsearch | # There is insufficient memory for the Java Runtime Environment to continue.
elasticsearch | # Native memory allocation (mmap) failed to map 2555904 bytes for committing reserved memory.
elasticsearch | # Can not save log file, dump to screen..
elasticsearch | # Out of Memory Error (os_linux.cpp:2651), pid=29, tid=0x00007337c59ab700

my memory situation is:
alpine:~/elastic$ free -m
total used free shared buffers cached
Mem: 7483 239 7244 0 34 128
-/+ buffers/cache: 75 7407
Swap: 4095 0 4095

What is the problem?
Java options used for container are:
"ES_JAVA_OPTS=-Xms512m -Xmx512m"

Thanks