Physical memory utilization is high

Hi All,

I am working on production environment having high end hardware specification.

My ETL and database are installed on two different servers.

DB server has MS SQL 2008

RAM  - 256 GB

with high end Processor.(didn't remember exact configuration)

Not able to recollect for ETL server also but definitely with high end hardware specification.

Now my question is even if we run single job the physical memory utilization of Production DB server shoots upto full utilization (all 253-254 GB).

Why does it happens ?

What are its consequences ?

What are the reasons causing so high memory utilization ?

Thanks in advance.

Regards,

Sachin