IBM DS3000 系列磁盘阵列,在使用单控制器且刷的单控NVSRAM的情况下仍然会出现写入缓存失效的问题。查看Logical Drives配置如下:

Read cache:                            Enabled
Write cache:                           Enabled (currently suspended)
Write cache without batteries:      Disabled
Write cache with mirroring:         Enabled (currently suspended)
Flush write cache after (in seconds):  10.00
Dynamic cache read prefetch:           Enabled

在双控制器的情况下,为了在一个控制器失效时不丢失数据,两个控制器的写缓存需互为镜像,防止丢失写缓存内容。但是在单控制器的情况下,显然是不需要写缓存镜像的,但是控制器却由于无法完成写缓存镜像因此暂停了写缓存,这会导致性能的巨大损失。使用命令“set allLogicalDrives mirrorEnabled=false;”可禁止写缓存镜像,运行后查看Logical Drives配置如下:

Read cache:                            Enabled
Write cache:                           Enabled
Write cache without batteries:      Disabled
Write cache with mirroring:         Disabled
Flush write cache after (in seconds):  10.00
Dynamic cache read prefetch:           Enabled