ASP.NET PDF Viewer using C#, VB/NET

To reduce response time, all the sorts that are performed in the PGA should be performed completely in the cache of the work area this is known as an optimal mode operation, since all work is done in memory, with no disk I/O whatsoever. If the sort operation spills onto the disk because the memory areas aren t adequate, that will slow down the sort operation. A SQL operation that is forced to use the disk area in a limited fashion is a single-pass operation, and it leads to slower performance than when the operation executes entirely in the memory cache. However, if your runtime memory area is too small relative to the sorting operation, Oracle will have to conduct multiple passes over the data being sorted, which is very disk intensive, and will result in extremely slow response times for the user. Thus, there is a direct correlation between the PGA size and query performance.

barcode font excel 2016, free barcode generator add-in for excel, excel 2010 barcode formula, barcode font excel 2003, free 2d barcode generator excel, how to change font to barcode in excel, barcode font excel 2007 download, barcode excel 2013 download, active barcode excel 2010, create barcode in excel 2016,

1. http://www.openwall.com/john/

Many Oracle manuals suggest that you can allocate up to half of the total system memory for the Oracle SGA. This guideline assumes that the PGA memory will be fairly small. However, if the number of users is very large and the queries are complex, your PGA component may end up being even larger than the SGA. You should estimate the total memory requirements by projecting both SGA and PGA needs.

As Table 7-4 shows, an access violation (0xC0000005) is automatically mapped to a System::AccessViolationException. This exception type has been introduced in .NET 2.0. In earlier versions of .NET, a System::NullReferenceException is thrown instead. Since this is a breaking change, you can switch back to the old behavior with the configuration file shown here: <configuration> <runtime> <legacyNullReferenceExceptionPolicy enabled="1"/> </runtime> </configuration>

You can tune the size of these private work areas, but this is a hit-or-miss approach that involves weighing a number of complex Oracle configuration parameters related to the work areas The parameters that you need to manually configure include the SORT_AREA_SIZE, HASH_AREA_SIZE, and BITMAP_AREA_SIZE parameters The sum of all the PGA memory used by all sessions makes up the PGA used by the instance Oracle recommends that you use automatic PGA management, which automates the allocation of PGA memory This helps you use the memory allocated to your database more efficiently The feature performs especially well when you have varying workloads, because it dynamically adjusts its available memory bounds and the work profiles on a continuous basis Manual management of PGA could easily lead either to too little or too much memory being allocated, which causes severe performance problems.

You automate PGA memory allocation by ensuring that the WORKAREA_SIZE_POLICY initialization parameter is set to its default value of auto If you set the parameter value to manual, you ll have to specify all the PGA work area related parameters mentioned previously The WORKAREA_SIZE_POLICY parameter ensures the automation of PGA memory However, you must also set the size of the total PGA memory allocation by specifying a value for the PGA_AGGREGATE_TARGET initialization parameter For example, if you set PGA_AGGREGATE_TARGET=5000000000 in your initialization parameter file, Oracle uses the 5GB PGA allocation as a global target for the instance Oracle will try to keep the total PGA memory used by all server processes attached to the instance under this target value If you don t set a value for the PGA_AGGREGATE_TARGET parameter, you ll be using the manual mode to manage the work areas.

Alternatively, you can activate the manual mode by setting the WORKAREA_SIZE_POLICY parameter to manual Oracle strongly recommends using automatic PGA management because it enables much more efficient use of memory For users, this means better throughput and faster response time for queries in general..

In a manual management mode, any PGA memory that isn t being used isn t automatically returned to the system. Every session that logs into the database is allocated a specific amount of PGA memory, which it holds until it logs off, no matter whether it s performing SQL operations or not. Under automatic PGA management, the Oracle server returns all unused PGA memory to the operating system. On a busy system, this makes a huge difference in database and system performance. Suppose you set the PGA_AGGREGATE_TARGET parameter to 5GB. Oracle will not immediately grab all of the 5GB when you start the instance, as it does in the case of the SGA_TARGET parameter. It will only take the memory as necessary from the system, subject to the limit of 5GB. As soon as a session releases the run-area memory, the memory is automatically released to the operating system.

The start of the script sets the variables for the current time and date. Since the epoch (1/1/1970) is fixed, its value can be calculated once and the constant 719591 used in its place, thus saving some CPU cycles.