Page 280 - Data Architecture
P. 280

Chapter 7.2: The Standard Work Unit
           uniform in size.”



           The SLA



           Related to the standard work unit is the notion of a service-level agreement or SLA. An
           SLA is an agreement stating what amounts to an acceptable level of performance and
           service in the online transaction environment.


           A typical SLA might look like the following:


               Mon–Fri, between the hours of 7:30 a.m. and 5:30 p.m.
                    All transactions will execute in no more than 3 seconds.
                    There will be no outages of greater than 5 minutes.


           The SLA covers both average response time and system availability. The SLA covers
           only working hours. Outside working hours, the computer operation staff is free to do
           whatever is needed to be done to the computer—running large statistical programs, doing
           maintenance, running database utilities, and so forth.












































                                                                                                               280
   275   276   277   278   279   280   281   282   283   284   285