缓冲池数据物理读数(以表空间页宽为单位定义)。
Buffer pool data physical reads (defined in units of tablespace page size).
缓冲池索引物理读数(以表空间页宽为单位定义)。
Buffer pool index physical reads (defined in units of tablespace page size).
缓冲池x da物理读数(以表空间页宽为单位定义)。
Buffer pool xda physical reads (defined in units of tablespace page size).
下面的例子定义了两个缓冲池和两个表空间,一个表空间的页宽为4KB,另一个表空间的页宽为32KB(注意,一个表空间总是要有一个缓冲池,且缓冲池要有一个匹配的页宽) 。
The following example defines two buffer pools and two table spaces, one each with 4KB and 32KB pages. (Note that a table space always requires a buffer pool with a matching page size.)
但是,如果总的缓冲区大小太大,并且没有足够的存储器可用来分配给它们,那么将为每种页大小分配最少的缓冲池,性能就会急剧下降。
However, if the total buffer size is too large, and there is not enough storage to allocate them, a minimum system buffer pool for each page size is allocated, and performance is sharply reduced.
如果有一些具有不同页大小的表空间,那么每种页大小必须至少有一个缓冲池。
If there are table Spaces with different page sizes, there must be at least one buffer pool per page size.
相反,表的页宽是由相应的缓冲池的页宽来确定的,这个缓冲池也就是为包含该表的表空间所指定的缓冲池。
Rather, the page size for tables is determined by the page size of the buffer pool to which the table space containing the table is assigned.
缓冲池是内存中的一块存储区域,用于临时读入和更改数据库页(包含表行或索引项)。
A buffer pool is an area of storage in memory into which database pages (containing table rows or index entries) are temporarily read and changed.
对于每个不同页大小的表空间,应该存在一个页大小相匹配的缓冲池。
For every different page size tablespace, there should be a matching page size buffer pool.
如果小型表拥有自己的缓冲池,那么它们就必须拥有自己的表空间,因此大型查询就不能覆盖它们的页。
If the small tables have their own buffer pool, thereby making it necessary for them to have their own table space, their pages cannot be overwritten by the large query.
如果的确是上述情况,那么使用更大的缓冲池是最好的解决办法,但是为索引页增加更多的自由空间也有所帮助。
If this is the case, a larger buffer pool is the best solution, but adding more free space to index pages may also help.
这个恢复进程立即开始将脏页从集中式缓冲池预取到它自己的本地缓冲池。
This recovery process instantly begins to prefetch dirty pages from the centralized buffer pool into its own local buffer pool.
在具有大缓冲池的环境下,也可能需要配置较多的页清除程序。
Environments with large buffer pools may also require more page cleaners to be configured.
这个计算考虑了缓冲池高速缓存的所有页(索引和数据)。
This calculation takes into account all of the pages (index and data) that are cached by the buffer pool.
假设有一个针对非常大的表运行的查询,它使用同一个缓冲池并且需要读取比总的缓存区大小还多的页。
You might also have a query that runs against a very large table that USES the same buffer pool and involves reading more pages than the total buffer size.
当您在大型审核日志表格中运行查询功能时,您可能会在您的数据库系统不得不向缓冲池读入数千页面以进行计算时而结束。
When you run queries for very large audit log tables, you can end up with a situation where your database system has to read thousands of pages into the bufferpool to compute the result.
这个变量指定防护例程调用(比如存储过程或用户定义函数调用)所使用的池的大小(以4KB页为单位)。
This variable specifies the size (in 4 KB pages) of the pool used for fenced routine invocations, such as stored procedure or user-defined function calls.
更少的缓冲池和表空间,以及更少的页宽种类,可以导致更简单的物理数据库设计,从而更容易管理、维护和调优。
Fewer buffer pools and table Spaces and fewer distinct page sizes lead to a simpler physical database design which is easier to manage, maintain, and tune.
而在其他平台上,缓冲池大小为250个页大小为4k的页。
For other platforms, the buffer pool size is 250 pages with a 4k pagesize.
请注意,缓冲池和表空间的页大小都是8K,两者是相同的。
Note that the page sizes of 8K for the buffer pool and table space are the same.
然而,过多地分配空余空间可能会产生浪费的DASD 空间,导致每次I/O 只能传输更少的数据,缓冲池的利用效率更低,并且要扫描更多的页。
However, over-allocating free space may result in wasted DASD space, less data transferred per I/O, less efficient use of buffer pools and more pages to scan.
缓冲池数据写远远大于异步池数据页写。
Buffer pool data writes is much greater than Asynchronous pool data page writes.
缓冲池索引写远远大于异步池索引页写。
Buffer pool index writes is much greater than Asynchronous pool index page writes.
当数据库启动时,要分配4个页宽分别为4k、8 K、16k和32 K的小型缓冲池。
Four small buffer pools of page size 4k, 8k, 16k and 32k are allocated when a database is started.
缓冲池索引写约等于异步池索引页写。
Buffer pool index writes is approximately equal to Asynchronous pool index page writes.
缓冲池数据写约等于异步池数据页写。
Buffer pool data writes is approximately equal to Asynchronous pool data page writes.
也可以使用新增的BUFFER POOL配置参数创建与dbspace页大小对应的缓冲池。
You can also use the new BUFFERPOOL configuration parameter to create a buffer pool that corresponds to the page size of the dbspace.
perl buffhitratio . pl dbrun. snap——该脚本提供了每个缓冲池的数据和索引页命中率。
Dbrun.snap - This script provides the hit ratio for the data and index pages of every buffer pool.
当您在UNIX平台上创建一个DB 2数据库时,一个默认的缓冲池IBMDEFAULTBP会被创建,它具有1000个页大小为4k的页。
When you create a DB2 database on UNIX platforms, a default buffer pool called IBMDEFAULTBP is created that is 1000 pages with a 4k pagesize.
db 2PageCleaner (db2pclnr):相当于Oracle中的DBWR进程,该进程在将页从磁盘上转移到BP中之前,清理缓冲池。
Db2 page Cleaner (db2pclnr) : Equivalent to DBWR process in Oracle, this process cleans the buffer pool before pages from the disk are moved into the BP.
应用推荐