竹科工程師( software engineer ) DIY Car Cefiro A32 的部落格(第二區)

Build Android AOSP get this error :

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space

some time the error "ninja failed with: exit status .....error, is cruse by this porblem.

this is two soution can sove this porblem.

1. buy more DDR memory to add your pc.

2. change JVM use monery space:

check my pc memory is :

cat /proc/meminfo

1 solve : my total memory is 8G, too smail for make AOSP, so can add 8G to 16G for this problem.

2. this let ours try to cange JVM use memory and swap size , check swapon size:

swapon -s 

change swap size this this command, close swap:

swapoff /swapfile

delete it:

rm /swapfile

make new and more big size swap:

sudo fallocate -l 20G /swapfile

  or 

sudo dd if=/dev/zero of =/swapfile bs=1024 count=10485760

mkswap /swapfile

Enable swap:

swapon /swapfile

Check swap:

swapon -show

change JVM use swap and memory 

echo 1 > /proc/sys/vm/overcommit_memory

This switch knows 3 different settings::

0: The Linux kernel is free to overcommit memory (this is the default), a heuristic algorithm is applied to figure out if enough memory is available.

1: The Linux kernel will always overcommit memory, and never check if enough memory is available. This increases the risk of out-of-memory situations, but also improves memory-intensive workloads.

2: The Linux kernel will not overcommit memory, and only allocate as much memory as defined in overcommit_ratio.

echo 75 > /proc/sys/vm/overcommit_ratio

Memory Allocation Limit = Swap Space + RAM * (Overcommit Ratio / 100)