- the rightmost single-digit, the number of the book’s printing.. - F Contents of the CD-ROM. - Characteristics of the OLTP System. - Characteristics of the Batch Processing System. - Characteristics of the Oracle Backup Process. - Review of the Library Cache. - The performance of the system depends on a number of factors. - The RDBMS consists of the database (the information) and the instance (the embodiment of the system). - The logical database consists of the following elements:. - The Oracle instance consists of the Oracle processes and shared memory necessary to access information in the database. - The infor- mation in the SGA is made up of the database buffers, the redo log buffer, and the shared pool;. - The PGA is made up of the following components:. - Many—if not all—the products Oracle offers use the RDBMS in one way or another. - Following is a list of some of the additional fea-. - The Parallel Query option is made up of the following components:. - Here’s a list of the development tools available:. - The person responsible for the operation and configura- tion of the database. - The DBA is the person responsible for the performance of the database. - The information in the SGA is made up of the data- base buffers, the redo log buffer, and the shared pool. - The response time is the meter by which the user judges the performance of the system. - Are the users satisfied with the performance of the system?. - Effective backup of the system is possible within a specified time interval. - A major difference between an OLTP system and a batch system is that—usually—the OLTP system has a constant. - If the load on the system is increased—caused by an unusually high number of users or an event such as a system backup or a checkpoint—the system should still be able to process transactions at nearly the same rate as during the typical system load.. - This chapter covers tuning methodology—the manner in which you analytically determine what it is you want to tune and for what ends. - Each system has deferent characteristics depending on the needs of the users. - Therefore, the throughput of the system is defined as follows:. - However, configuring for load time may affect the general performance of the system. - You may just be at the limits of the configuration. - However, you should still periodically monitor the performance of the system to avoid future problems.. - try to determine the root of the problem or bottleneck.. - Full disclosure of the system configuration, cost, and benchmarking methodology.. - It is also charged with the administrative and support activities of the council.. - Here are some of the significant rules:. - These properties guarantee the integrity of the system and add credibility to the benchmark results. - The following section looks at the benchmarks that have come out of the TPC.. - This requirement significantly increases the size of the system being priced.. - This second metric is designed to demonstrate the value of the system.. - The TPC-C benchmark employs five different transaction types that stress different areas of the system. - These five transactions make up the workload of the TPC-C benchmark. - Generation of intense activity on the part of the server component under test. - The performance metrics used in the TPC-D benchmark measure different aspects of the ca- pability of the system. - The first metric used in the TPC-E benchmark is the Maximum Qualified Throughput (MQTh)—the number of New-Order transactions per minute, which is reported as tpmE.. - This second metric is designed to demonstrate the value of the system. - Individual results are in the form of the Executive Summary. - Company: The sponsor of the benchmark. - System: The name and model number of the benchmarked hardware.. - The performance of the system.. - Database software: The name and version of the database software used in the benchmark.. - Operating system: The name and version of the operating system used in the benchmark.. - TP monitor: The name and version of the TP monitor used in the benchmark.. - System: The name and model number of the benchmarked hardware. - Qty/Processors/MHz: Describes the number, type, and speed of the CPUs in the system.. - During this phase, it is important to take careful notes on the progress of the benchmark. - From Server Manager, you can display much of the information available in the V$ tables.. - These are but a few of the important indicators you will require in the upcoming chapters.. - In the design stage, it is important to look not only at the application and the database but at the sizing of the system as well. - The design of the application can also be a deciding factor in the future performance of the system. - These problems can be caused by any of these parts of the system:. - It is the job of the performance engineer to re- duce or eliminate bottlenecks.. - Finally, the performance of the system is limited by how fast the system can go. - Even with the most optimally tuned system, you are limited by the speed of the system’s CPUs. - the system performance relies on the speed of the CPUs, as it should.. - in the case of the cost-base approach, the same optimization goal must be used.. - You can check the efficiency of the data dictionary cache. - Listing 9.2 The Results of the Query in Listing 9.1. - With the exception of the CKPT process, only the DBWR writes to the data files.. - In many cases, the performance of the system is entirely limited by disk I/O. - u NAME: The name of the data file.. - u BYTES: The size of the data file.. - The size of the data files depends on the size of your tables. - The size of the volume is (n - 1)*Disk Size where n is the number of drives in the set.. - u Performance is improved because of the drop in the number of migrated and chained rows.. - A Review of the PCTFREE and PCTUSED Options. - Average Row = 100 or 5 % of the data block ( 100 - PCTFREE. - The rollback segment is assigned for the duration of the transaction.. - The number of extents used for the rollback segments is determined in the definition of the rollback segments when you create them. - There is probably very little dynamic growth of the extents.. - u RSSIZE: The size in bytes of the rollback segment.. - This data must be available for the entire length of the transaction. - the size of the redo log buffer should be in- creased. - These blocks are tagged on to the normal activity of the DBWR. - In the case of the normal checkpoint, transaction processing is not as affected as it is with the fast checkpoint. - Archiving usually has very little effect on the performance of the system—but there are some cases in which performance can be affected. - Here is a summary of the goals discussed in this chapter:. - The larger block size may benefit the overall performance of the system.. - Fragmentation occurs when pieces of the database are no longer contiguous. - The number of hash values is determined by the HASHKEYS value parameter of the CREATE. - u The size of the table is static. - u The value of the cluster key does not change.. - Use indexes when queries access less than 5 percent of the rows in the table.. - The size of the I/Os depends on both. - The optimizer determines the execution plan of the statement.. - u The capacity of the system to handle large numbers of processes. - u The I/O capacity of the system. - By designing the system properly, you can take maximum advantage of the parallel server features.. - This chapter looks at many of the features you can enable in the server operating system. - The priority of the process is also of importance. - Be careful of the restrictions associated with PSE memory. - Remember the concept of the checkpoint
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