How do I create a ramdisk ?

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How do I create a ramdisk ? From: Mark Grubbs

# mkramdisk SIZE
/dev/rramdiskxx
# mkfs -V jfs /dev/ramdiskxx
# mount -V jfs -o nointegrity /dev/ramdiskxx /whatever

[Editor's notice: This function is new in 4.3.3 ]
[Editor's notice: This function is UNSUPPORTED ]

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