FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory in Ionic 3

Question

When I run an Ionic 3 project using the ionic serve command, then I am getting this error:

Answer 1

For a non-angular general answer for those who land on this question from Google:

Every time you face this error its probably because of a memory leak or difference between how Node <= 10 and Node > 10 manage memory. Usually just increasing the memory allocated to Node will allow your program to run but may not actually solve the real problem and the memory used by the node process could still exceed the new memory you allocate. I'd advise profiling memory usage in your node process when it starts running or updating to node > 10.

I had a memory leak. Here is a great article on debugging memory leaks in node.

That said, to increase the memory, in the terminal where you run your Node process:

export NODE_OPTIONS="--max-old-space-size=8192"

where values of max-old-space-size can be: [2048, 4096, 8192, 16384] etc

[UPDATE] More examples for further clarity:

export NODE_OPTIONS="--max-old-space-size=5120" #increase to 5gb
export NODE_OPTIONS="--max-old-space-size=6144" #increase to 6gb
export NODE_OPTIONS="--max-old-space-size=7168" #increase to 7gb
export NODE_OPTIONS="--max-old-space-size=8192" #increase to 8gb

# and so on...

# formula:
export NODE_OPTIONS="--max-old-space-size=(X * 1024)" #increase to Xgb

# Note: it doesn't have to be multiples of 1024. 
# max-old-space-size can be any number of memory megabytes(MB) you have available.