Hardware Installation
PixelStor 5000 User Manual
Rev. 1, May 2013
7-91
6.2
Cache Settings Defined
Write-back Cache Option
- Data normally written to disk is first written into the cache.
During idle machine cycles, the data is written from the cache into disk.
Pros- Improves performance because a write to the cache is faster than to disk.
Reduces the number of write operations to disk.
Cons- With this performance improvement comes a risk that data may be lost if the
system crashes. The write back cache configuration should only be selected if you have
the battery-backed option installed.
Write Through Cache Option
-
Data is written to disk and also written into the cache.
Pros
– This method ensures complete data integrity and good performance for
sequential access, which relies on less cache. If a subsequent read operations need
that same data, read performance is improved, because the data is already in the
cache.
Cons- Write performance is not improved with this method.
Auto Cache Setting -
This RASILIENT setting automatically turns on write back cache
and enables the mirrored cache feature with two controllers installed. If the second
controller is removed or fails, the system automatically switches to a write through cache
configuration.
Pros - Good cache performance and complete data protection.
Cons
– Less optimized performance for sequential access due to mirrored cache
system overhead.
7
Appendix B – Using the Command Line Interface (CLI)
7.1
Preparing to use the CLI
The following information is for experienced users that wish to manage the
PixelStor 5000
with the built in Command Line Interface using:
A terminal connected to the Serial port of the
PixelStor 5000
or
A Telnet session to the
PixelStor 5000
