【正文】 y. A batch run consists of multiple independent batch jobs that are scheduled for execution on a recurring basis. A large anization may execute multiple batch runs throughout the day depending on the resources required to process them. Each batch job consists of multiple batch job steps that control specific activities of job execution. An anization typically processes numerous batch jobs. To ensure a consistent approach to the execution of each job, a batch job skeleton should be devised that Batch Job Batch Run Batch Job 1 Batch Job 2 Batch Job 3 Batch Step 1 Batch Step 2 Batch Step 3 Service Management Function 13 contains the standardized code required for each job。 Operations Framework (MOF). The guide assumes that the reader is familiar with the intent, background, and fundamental concepts of MOF as well as the Microsoft technologies discussed. An overview of MOF and its panion, Microsoft Solutions Framework (MSF), is available in the MOF Service Management Function Overview guide. This overview guide also provides abstracts of each of the service management functions defined within MOF. Detailed information about the concepts and principles of each of the frameworks is also available in technical papers available at 3 Job Scheduling Overview Job scheduling involves the continuous anization of jobs and processes into the most efficient sequence, maximizing system throughput and utilization to meet service level agreement (SLA) requirements. Job scheduling is closely tied to service monitoring and control and to capacity management. Job scheduling entails defining: ? Job schedules. The workloads are broken down into time periods (daily, weekly, monthly, annually) and jobs are scheduled for execution according to business needs, length of job, storage requirements, and associated dependencies. ? Scheduling procedures. Schedules are set up and maintained, conflicts and problems pertaining to scheduling are managed, and special needs (such as asneeded jobs) are acmodated. ? Batch processing. Jobs are executed according to the work schedule, run priority, and job dependencies. Batchprocessing procedures include: ? Job documentation ? Hardware instructions (for example, tape units, data cartridge units, and printers) ? Console operations ? Control checks ? Problem management Goal and Objectives The goal of job scheduling is to ensure the successful execution of batch processes at a time that minimizes the impact on interactive users of system resources. The main objectives of job scheduling include monitoring, analysis, tuning, and implementation of batch runs. 6 Job Scheduling Scope Job scheduling ensures the successful execution of batch runs while minimizing the impact on users of system resources: ? Job scheduling establishes batch schedules and maintains batch job standards, ensuring that operational level agreements (OLAs), service level agreements (SLAs), and resource thresholds are not breached. ? Job scheduling manages, tests, and implements changes to the schedule via change management, taking account of changes to the scheduling calendar (holidays, for example) and the targets detailed in the OLAs in place. ? Job scheduling monitors and controls the batch schedule, ensuring that batch runs do not affect the live service. It monitors the oute of successful or unsuccessful batch jobs and establishes alert, error, and event management processes. It also identifies baselines for job scheduling performance. ? Job scheduling implements asneeded requests, ensuring that the existing schedule is not adversely affected. It is responsible for the analysis and correction of batch process errors, implementing job performance analyses, and tuning batch processes. It also ensures that all changes to the batch schedule are implemented through change management processes. Key Definitions Alert. An indication of a significant event. Alerts are defined by processing rules. Baseline. A frozen “picture” of the IT environment at a set point in time that identifies the structure of the IT environment and the underlying dependencies of the ponents of that environment. From an availability management perspective, the term also is used to identify an agreed set of availability definitions and targets for an IT service. Such definitions and targets normally will have been proved through modeling and, once defined, will be used as key availability design and reporting criteria. Batch system. A system that takes a set of mands or jobs, executes them, and returns the results, all without human intervention. This contrasts with an interactive system where the user’s mands and the puter’s responses are interleaved during a single run. A batch system typically takes its mands from a disk file (or a set of punched cards or magic tape in the past) and returns the results to a file (or prints them). Often there is a queue of jobs that the system processes as resources bee available. Error detection. A technique for detecting when data is lost during transmission. This allows the software to recover lost data by notifying the transmitting puter that it needs to retransmit the data. Event. Any significant occurrence in the system or an application that requires users to be notified or an entry to be added to a log. Job scheduling. A MOF service management function in the Operating Quadrant. It involves the continuous anization of jobs and processes into the most efficient sequence, maximizing system throughput and utilization to meet SLA requirements. Task scheduler. System or application that automatically invokes scripts or programs at specified times 4 Processes and Activities This chapter provides a detailed discussion of the processes and activities that occur in the Job Scheduling SMF. Process Flow Summary