For 800xA History, is it possible to have the "Real Time Database" and the "On-line Backup" on RAID 5
For 800xA History 2.0 / 6.0, is it possible to have the "Real Time Database" and the "On-line Backup" on the same RAID 5 hard drive configuration in separate partitions ? (for a small system)
Thanks in advanced
Voted best answer
Can you ? - Yes
Should you ? - No. History is a disk intensive operation.
>"While RAID 5 is deprecated and should never be used in new arrays, I include it here because it is a well-known and commonly-used RAID level and its performance needs to be understood. RAID 5 is the most basic of the modern parity RAID levels. RAID 2, 3 & 4 are no longer found in production systems and so we will not look into their performance here. RAID 5, while not recommended for use today, is the foundation of other modern parity RAID levels so is important to understand.
Parity RAID adds a somewhat complicated need to verify and re-write parity with every write that goes to disk. This means that a RAID 5 array will have to read the data, read the parity, write the data, and finally write the parity. Four operations for each effective one. This gives us a write penalty on RAID 5 of four. So the formula for RAID 5 write performance is NX/4.
So following the eight spindle example where the write IOPS of an individual spindle is 125 we would get the following calculation: (8 * 125)/4 or 2X Write IOPS which comes to 250 WIOPS. In a 50/50 blend this would result in 625 Blended IOPS."