Pillar Data and Xiotech are much better at providing storage for 8,000 Exchange 2007 users than the competition in terms of drive spindle needs and response latency.
Microsoft has encouraged its storage partners to run benchmarks at varying levels of Exchange user populations for both Exchange 2007 and 2010. We looked at the Exchange 2007 with 8,000 users level and saw results from Compellent, EMC, HP, IBM, Pillar and Xiotech. These results were compared on the basis of the number of drives used and the percentage storage capacity used by the database, as they met the Microsoft-specified test needs of supporting 8,000 users with a heavy workload of 0.48 IOPS/mailbox/sec.
Compellent put up a Storage Center v4.2 setup with 40 300GB, 15K, Fibre Channel drives - 37 for the database and 3 hot spares - and revealed that 63 per cent of the storage capacity was allocated to the Exchange database.
An EMC Celerra NS20 needed 48 drives and 31.7 per cent of the capacity was allocated to the database. HP furnished an EVA4400 with 46 drives and 49 per cent of their capacity used by the database. An IBM DS4700 Express needed 48 drives with 47 per cent of the space given over to the database. These three are roughly similar.
Pillar, choosing for some reason an 8,500 Exchange user level, put up an Axiom 600 with 78 drives. What was going on here? There were, in fact, only 26 hard disk drives: ponderous 7,200rpm, 500GB SATA ones at that. The other 52 drives were 50GB solid state drives. The consequence of this was that the Axiom ran three times faster than the targeted workload, at 1.63 IOPS/mailbox/sec, and its latency was, Pillar says, dramatically lower than the competition. The capacity used by the Exchange database was 85 per cent.
There was no NetApp result at the 8,000 user level, although NetApp had results across the 4,000-60,000 users range. 3PAR saved its efforts for the Exchange stratosphere level with 24,000, 48,000, and 96,000 user level runs.
Xiotech met the 8,000 user test requirements with an Emprise 5000 having just 20 spindles - 15,000rpm 326GB drives, and the percentage of the storage capacity used by the Exchange database was 94.7 per cent. That seems to be the most efficient storage of the group, at this user level, with Pillar's Axiom being the fastest. ®