Reboot host-system from container:
[root@box ~]# echo b > /proc/sysrq-trigger
Other things
m - Will dump current memory info to your console.
[root@box ~]# echo m > /proc/sysrq-trigger
dmesg On the host:
[18529.421008] sysrq: SysRq : Show Memory
[18529.421016] Mem-Info:
[18529.421028] active_anon:398347 inactive_anon:124929 >isolated_anon:0
active_file:83056 inactive_file:84631 >isolated_file:0
unevictable:0 dirty:255 writeback:0 unstable:0
slab_reclaimable:9008 slab_unreclaimable:99856
mapped:93061 shmem:125442 pagetables:7025 >bounce:0
free:52856 free_pcp:1169 free_cma:0