[CentOS] Suggestions for partition

[Feizhou]

Andreas Micklei wrote:
> Am Mittwoch, 9. Mai 2007 schrieb Feizhou:
>>> HW vs SW RAID: Kind of a religious question. HW has some advantages when
>>> using RAID-5 or RAID-6 (less CPU load). When using RAID-0 or RAID-1 there
>>> should not be any difference performance wise. HW RAID gives you some
>>> advantages in terms of handling, i.e. hotplugging of discs, nice
>>> administration console, RAID-10 during install ;-), etc. It's up to you
>>> to decide whether it is worth the money. Plus you need to find a
>>> controller that is well supported in Linux.
>> Hardware raid that comes with bbu write caches normally have a speed
>> boost in addition to the extra data safety too.
> 
> Also on RAID-0 and RAID-1? I have only used HW RAID without bbu, so I have no 
> experience with that. However you can tweak your filesystem and disks to do 
> write caching too, especially if you have plenty of RAM. Of course this means 
> living dangerously, so when you need performance and data safety HW RAID with 
> bbu is the only option of course.

Why did you think I specifically said hardware raid that comes with bbu 
memory caches? RAM will always be faster than disk so if the hardware 
raid stores stuff first in a bbu memory cache, it will always beat 
software raid even on raid0,raid1.

Hardware raid without a bbu memory cache will always be slower on raid5 
even if the raid processor is beefy enough.