You work as a design specialist at Certkiller .com. Certkiller .com has a four-member cluster that contains nine months of cellular/mobile phone provider data. The system controls network authorization, performs fraud analysis, produces reports and final billing feeds. Workloads include incoming data from cell towers and real-time account recalculation results. Network traffic continues to increase.
Mirrored BCVs and SRDF protect the data.
1. Supporting storage is spread across six Symmetrix 8430s and five Symmetrix 8530s using 36 G and 73 G drives, respectively.
2. 35.2 G meta-volumes used in a double-stripped 4×768 K configuration.
3. Cell related IOPS during peak use hours range from 12 to 30 K per array. Marketing sold consolidation to a single DXM 3000 with 146G drives using RAID 5 to reduce TCO and provide 18 months of growth.
What would be your primary design concerns?
A.
Access density.
B.
Backplane capacity.
C.
Growth calculations.
D.
Underlying network capacity.
E.
Front-end random arrival rate.
Explanation:
Access Density is the ratio of performance, measured in I/Os per second, to the capacity of the drive, usually measured in gigabytes (Access Density = I/Os per second per gigabyte). Since we are going from 36/73GB drives -> 146GB, the Access Density will grow significantly and might outstrip the actual drive performance maximum.