Create a snapshot trace buffer

configname: CONFIG_TRACER_SNAPSHOT

Linux Kernel Configuration
└─>Kernel hacking
└─>Tracers
└─>Create a snapshot trace buffer
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Allow tracing users to take snapshot of the current buffer using the
ftrace interface, e.g.:

echo 1 > /sys/kernel/debug/tracing/snapshot
cat snapshot