All entries for Saturday 11 February 2006
February 11, 2006
- One very good point is multiplexing online log and control file even you are using RAID 0+1 (stripe & mirror)
- RAID 0+1 for undo space since it cannot be multiplexed, read/write frequently
- RAID 5 or 0+1 for datafile,
The result of df -h on our serve:
is every entry a paired disk?
If not, how to check, fdisk?
The relationship of controller and disk, 1 to 1 ?
the IO speed decided by controller , I guess ? Then how controller interact with the disks?
Also see: link
0+1 and 1+0 have same performance. 1+0 has better availability.
What we use then ?
RAID 0: no reliability; improve performance
RAID 1: provides the highest performance for redundant storage
RAID 2: No implementation
RAID 3: Not good for database
RAID 4: Performance no better than 5
RAID 5: Parity RAID allows redundancy with less total storage cost. The loss of a single disk will cause read performance to be degraded while the system reads all other disks in the array and recomputes the missing data.