RAID Levels
19
Figure 1-12
Distribution of User and Parity Data in a RAID-5 Group
For each write operation to a RAID-5 group, the CHALLENGE RAID
storage system must perform the following steps:
1.
Read data from the sectors being written and parity data for those
sectors.
2.
Recalculate the parity data.
3.
Write the new user and parity data.
...
Fifth module
Parity
Fourth module
384-511
896-1023
...
1408-1535
Third module
256-383
768-895
1792-1919
1280-1407
2048-2175
1920-2047
2304-2431
2432-2559
128-255
640-767
1152-1279
2176-2303
1664-1791
...
...
Parity
Parity
Parity
1024-1151
512-639
1536-1663
Parity
First module
Second module
Blocks
0-127
Stripe
Stripe
element
size
Stripe size
=
User data
=
Parity data
...