https://excessivelyadequate.com/posts/history.htmlTLDR; Add to your .bashrc or .bash_profile:
#Read this number of lines into history buffer on startup.
export HISTSIZE=1000000
#`HISTFILESIZE` is usually set
after bash reads the history file (which is
#done after reading any configs like `.bashrc`). If it is unset at this point,
#it is set to the same value as `HISTSIZE`. Therefore we must set it to `NIL`,
#in which case it isn't "unset", but doesn't have a value either, enabling us
#to keep an unlimited history.
export HISTFILESIZE=""
