job160scheduling(编辑修改稿)

job160scheduling(编辑修改稿)内容摘要：

zen “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 Job scheduling prises four main processes and a number of subprocesses as follows:  Batch architecture  Management server  Capacity database (CDB)  Application servers  Monitor and printer  Batch processing  Job scheduling activities  Monitoring  Analyze  Tuning  Implementation  Event management  Asneeded request handling  Schedule changing  System backup  Archiving  Auditing  Capacity manager log entry  Reporting  Documentation and training 8 Job Scheduling The following figure shows a process flow for job scheduling. Figure 1. Process flow diagram for job scheduling Batch Architecture Before a discussion of daily operational batch activities can begin, the basic ponents that make up the batch architecture should be understood. A batch architecture consists of the processes and ponents used to effectively manage batch processing. This section is a brief introduction to the typical ponents found in batch architecture. The purpose of the batch architecture is to optimize processing (improve response time and utilization of system resources) by executing batch runs during offpeak periods. The architecture should provide the capacity manager with an easy to use interface and permit a standard and centralized approach to batch scheduling, monitoring, control, and error correction. The architecture should be highly scalable in order to meet the future needs of the anization. It should also be highly available, with minimal downtime, and minimize impact to online operations, which usually are operating concurrently with the batch operations. Some anizations may decide to have backup ponents, such as the event server, to ensure the pletion of all missioncritical batch jobs. Activ ities Training Start Batch Architecture Batch Processing Job Scheduling Documentation and End Service Management Function 9 Figure 2 shows the basic ponents of the batch architecture, which include the management server, capacity database (CDB), monitor, printer, application servers, and databases. In addition to the monitor attached to the management server, each application server should have a monitor to permit viewing of local batchprocessing activity。 this also facilitates error analysis at the local level. Figure 2. Simplified view of a batch architecture Management Server The heart of the batch architecture is the management server on which resides the batch scheduling tool. This tool permits the automatic execution of predetermined scheduled batch runs. Application Server Application Server Management Server Application Server Data Monitor Data CDB Printer 10 Job Scheduling The scheduling tool can typically perform the following functionality automatically:  Start and stop jobs based on date, time, day of the week, frequency, and so on.  Define, maintain, and manage job queues.  Prioritize jobs in queue.  Assign jobs to specific servers based on availability.  Track status of jobs and allow realtime monitoring.  Perform error recovery during batch runs.  Report and log errors.  Generate reports.  Archive reports and purge outofdate reports and log files.  Graphically display all information.  Display job history. Note that the functionality of scheduling tools varies greatly. While some tools may be able to execute the tasks listed above, other tools may only be able to start a batch run at a particular time. Sophisticated scheduling tools should permit the capacity manager the ability to:  Change schedules.  Change jobs.  Change job priorities.  Start and stop jobs.  Recover or restart failed jobs.  Initiate asneeded jobs.  Generate reports. The user interface of the scheduling tool should be easy for the capacity manager to interpret and use. The capacity manager should have the ability to perform the functional capabilities described above from a centralized location. From this location, the capacity manager。