Db2 bufferpools and the linux file cache perform largely the same function ; that is , cache a copy of data read from disk Db2缓冲池与linux文件缓存基本上执行相同的功能,也就是缓存从磁盘读出的数据的拷贝。
As noted earlier , the flow of reads under normal circumstances is to read into the file cache and then copy into the bufferpool 如前所述,一般情况下,读操作的流程是先将数据读到文件缓存中,然后再复制到缓冲池。
Direct i o solves this issue by directing reads to be made directly from disk into db2 memory areas , bypassing the file cache entirely 直接i / o直接将数据从磁盘读到db2内存区域,完全绕过文件缓存,从而解决了上述问题。
Prior to the linux 2 . 6 kernel , file caching on a linux system could go awry , using a huge number of cycles trying to manage the file cache 对于linux 2 . 6之前版本的内核, linux系统上的文件缓存可能会出差错,需要花费大量的周期来管理文件缓存。
Memory utilization and file caching are related elements that affect performance and are important to consider when tuning a database system 内存的使用和文件缓存是彼此相关的两个部分,它们一起影响着性能,在对数据库系统进行调优时,要重点考虑这两个方面。
If a user adds changes to a replicated file cached somewhere else , the original file server will activate the callback and remind the original cached version that it needs to be updated 如果用户更改了缓存在其他地方的复制文件,原始文件服务器将会激活回调,并提醒原始缓存版本它需要更新。
This feature is available on a tablespace - by - tablespace basis , effectively allowing some data in db2 to use file caching and other data to bypass it . the tablespace option no file system caching 这个特性是以表空间为单位启用或禁用的,从而可以有效地使db2中的某些数据使用文件缓存,而另一些数据则绕过文件缓存。
Memory allocated to the file cache can be reduced and given to requesting processes , reducing the amount of data being buffered ; however , read and write requests still pass through the smaller file cache 可以削减分配给文件缓存的内存,并转给发出请求的进程,这会减少被缓冲的数据量;但是,读写请求仍然会经过这个更小的文件缓存。
One of the niche products is the new - generation file caching storage products - solid state disc - which further enriches the company s capability to provide data centers with comprehensive solutions 其中一项崭新产品,是新一代档案快取file caching存储产品ssd solid state discs 。利用ssd ,公司能向客户提供全面的数据中心解决方案。
One of the niche products is the new - generation file caching storage products - solid state disc - which further enriches the company s capability to provide data centers with comprehensive solutions 其中一项崭新产品,是新一代档案快取( filecaching )存储产品ssd ( solidstatediscs ) 。利用ssd ,公司能向客户提供全面的数据中心解决方案。