[mythtv-users] recommendations for building new FE/BE HDTV system?

[Tyler T]

>> I don't mean to answer for the person to whom the question was directed, but I
>> can tell you why I use RAID0 instead of Storage Groups.
>>
>> RAID0 will increase the performance of the disk system, while Storage Groups

I was the person to whom the question was directed, and the answer is
I was not aware of the Storage Groups feature when I did my Myth
installation. However, even if I had, I probably still would have used
RAID-0. I have old PATA drives... I don't recall the speed right now,
but they might even be 5400rpm. And although Myth will save concurrent
recordings on parallel Storage for a performance boost, Raid-0 has the
advantage of improving the speed of transcoding jobs and other things
you happen to use the array for.

>> I'm not sure why the RAID array is more than twice as fast as the single
>> drive, but it appears to be, at least according to this somewhat limited
>> test.

> The simple reason why it's faster is that this is what RAID-0 is
> designed to do; it stripes the data across multiple disks so that you

I think his surprise was more due to the 3X increase in speed, rather
than the expected 2X increase. However if you view the Raid-0
performance as the baseline, it becomes more a question of why the
single drive is 1/3 the speed instead of 1/2. Perhaps part of it is
due to Raid-0 effectively doubling the amount of on-drive cache and/or
other efficiencies having to do with seeking algorithms using multiple
heads etc. The md devs may have a few tricks up their sleeve in that
department.
___
 /yler