To check the size and amount of Huge Pages use:
grep -i Hugepage /proc/meminfo
This should so something like:
HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 2048 kB
To change the number of HugePages use the following:
sysctl -w vm.nr_hugepages=2560
This would allocate 2560x2048kB = 5GB
grep -i Hugepage /proc/meminfo
AnonHugePages: 10240 kB HugePages_Total: 2560 HugePages_Free: 2560 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 2048 kB
To check the impact on memory:
grep -i memfree /proc/meminfo
Reset Huge Pages
The change can be applied permanently in /etc/sysctl.conf but to switch the number of Huge Pages back to zero:
sysctl -w vm.nr_hugepages=0
And check again with:
grep -i Hugepage /proc/meminfo grep -i memfree /proc/meminfo
