Default number of RAM disks

configname: CONFIG_BLK_DEV_RAM_COUNT

Linux Kernel Configuration
└─>Device Drivers
└─>Block devices
└─>Default number of RAM disks
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
The default value is 16 RAM disks. Change this if you know what you
are doing. If you boot from a filesystem that needs to be extracted
in memory, you will need at least one RAM disk (e.g. root on cramfs).