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{{UBC toc}}
The [[UBC consistency check]] article discussed validation of a resource control [[UBC]] configurationfor a single container. This article discusses checks that the UBC configuration of the
'''whole''' system is '''valid'''.
The best way to make sure that the configuration of the whole system
is valid is to run periodic automatic checks, based on the formulae described
below. {{Man|vzmemcheck|8}} utility can be helpful in calculations.
== Resource utilization and commitment level ==
containers at the given time.
In general, low utilization values mean that the system is under-utilized.
Often, it means that the system is capable of supporting more VirtualcontainersEnvironment if the existing containers continue to maintain
the same load and resource consumption level.
High utilization values (in general, more than <code>1</code>)
overcommitted.
If the system runs a lot of containers,
it is usually acceptable to have some overcommitment, because it is unlikely that all VirtualEnvironments containers will request resources at the same time.
However, higher commitment levels (as discussed below for each resource
individually) will cause containerss to experience failures to
allocate and use the resources promised to them.
== “Low memory” (x86 x86_32 specific) ==
Because of specifics of architecture of Intel's x86 processors, the RAM of the
computer can't be used uniformly.
The normal commitment level is about <math>0.8</math>—<math>1</math>.
Commitment levels more than <math>1</math> means that the Virtual Environmens containers are
guaranteed more memory than the system has.
Such overcommitment is strongly not recommended, because in that case
It is better to guarantee containers less and have less commitment
levels than to accidently accidentally overcommit the system by memory plus swap.
If the system has spare memory and swap, containers will
transparently be able to use the memory and swap above their guarantees.
However, for stability-critical applications, it's better to keep
the level not exceeding <math>1</math>.
<references/>