[CentOS] C6 server responding extremely slow on ssh interactive

Fri Jan 30 09:39:36 UTC 2015
Patrick Bervoets <patrick.bervoets at psc-elsene.be>

Op 30-01-15 om 10:29 schreef John R Pierce:
> On 1/30/2015 1:21 AM, Patrick Bervoets wrote:
>> free
>>              total       used       free     shared buffers cached
>> Mem:         48218      31895      16323          0 108 519
>> -/+ buffers/cache:      31267      16951
>> Swap:         7951        476       7475
>
> thats an unusually small amount of 'cached'...  I usually see the disk cache as 30-50% of the total memory.  does this system not use much disk IO 

it's a kvm-host with lvm, the vm's all have there own lv's (some on a different pv). Would that explain the small cache?