Preload is a daemon which monitors “adaptive readahead daemon” which analysises and monitors most used programs in the background. Once it knows this information, it will load them into memory so that when they are run, it’s already in memory and ready to go.
It will only use unused RAM so there should be no performance degredation with the exception of a small overhead for analysising the frequently used programs. This is good way to speed application starting up if the system has a lot of (unused)memory but a slow HDD.
sudo apt-get install preload
It may require a restart before it takes effect.