Can't increase Mac OSX bash shell history length
Solution 1:
You also need to set HISTSIZE=10000000.
HISTFILESIZE determines the number of lines to keep in the history file while HISTSIZE determines the number of lines to keep in memory. Both default to 500
Execute echo $HISTFILESIZE $HISTSIZE before you make the change and then again after. You should see 10000000 500 first then 10000000 10000000 after.
Solution 2:
You need to export HISTSIZE and HISTFILESIZE environment variables in your ~/.bash_profile file.
Add following lines in your ~/.bash_profile:
# history size
export HISTFILESIZE=1000000
export HISTSIZE=1000000