[pve-devel] [PATCH 1/2] add hugepages option

[Alexandre DERUMIER]

>>In my experience, it always works, but you might end up with a unresponsive 
>>system for minutes/hours/days, because it swaps out the memory (if you have 
>>enough), which is in the way. I killed at least two machines with this. 
>>Therefore, I always configure hugepages and do a reboot. This way I will 
>>not end up in a totally messed up system. 

I'm planning to check swap too, to avoid alloc too many pages

I have just done a test, allocating 1GB hugepage

# free
              total       utilisé      libre     partagé tamp/cache   disponible
Mem:       16340948     1812388    13437880      265344     1090680    13954632


#echo 14 > /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages

(should overload)

#cat /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages

->9

# free
              total       utilisé      libre     partagé tamp/cache   disponible
Mem:       16340948    11260360     4005652      249008     1074936     4522816
Partition d'échange:           0           0           0


As I don't have enough contigous memory, all 1GB hugepages can't be allocated.


Of course, with 2MB, it's a lot more easier.