Home > Workload Solutions > SAP > Guides > SAP HANA TDI Guides > Dell Validated Design for SAP HANA TDI with Dell PowerVault ME5 Storage > PowerVault drive configuration
For SAP HANA, Dell Technologies recommends using SSDs with a disk capacity size that allows the system capacity to fit within the base enclosure. Dell engineering has tested SAP HANA performance and scalability on a PowerVault ME5024 system (a four-port 32 Gb FC per controller) and observed that a PowerVault ME5024 or ME5084 array supports up to 14 HANA nodes with 18 SSDs in single parity (single tolerance R5), a virtual or linear ME5 storage pool. ADAPT and RAID 6 RAID configurations can have a significant impact on SAP HANA scalability performance when compared to RAID 5, so expect a reduced SAP HANA scalability node count of approximately 40 percent to meet the SAP HANA KPIs.
For SAP HANA scalability on PowerVault ME5 arrays in production, see Table 3.
The following table describes the characteristics of each RAID level that is supported in PowerVault ME5 storage systems:
RAID level | Protection | Performance | Capacity utilization |
RAID 1/ RAID 10 | Protects against up to one disk failure per mirror set | Great random I/O performance | Poor: 50 percent fault tolerance capacity loss |
RAID 5 | Protects against up to one disk failure per RAID set | Good sequential I/O performance, good random read I/O performance, moderate random write performance | Excellent: One-disk fault tolerance capacity loss |
RAID 6 | Protects against up to two disk failures per RAID set | Good sequential I/O performance, good random read I/O performance, moderate random write performance (lower than RAID 5) | Moderate: Two-disk fault tolerance capacity loss |
ADAPT | Distributed erasure coding with dual disk failure protection supports 16+2 or 8+2 stripe width. | Very fast rebuilds, no spare disks (integrated spare capacity), large storage pools, simplified initial deployment and expansion | Zero percent of capacity used for fault tolerance for8+2; 11.1% of capacity used for fault tolerance for 16+2 |
For information about disk counts per RAID level, see the “Best practices” section in the Dell PowerVault ME5 Series Administrator's Guide.
The following table shows recommended disk counts for RAID 6 and RAID 5 disk groups. Each entry specifies the total number of disks and the equivalent numbers of data and parity disks in the disk group. Parity is distributed among all the disks.
RAID level | Total disks | Data disk (equivalent) | Parity disk (equivalent) |
RAID 6 | 4 | 2 | 2 |
6 | 4 | 2 | |
10 | 8 | 2 | |
RAID 5 | 3 | 2 | 1 |
5 | 4 | 1 | |
9 | 8 | 1 |
Use power-of-two data disks to ensure best performance with sequential workloads and RAID 5 and RAID 6 disk groups. Also, Dell Technologies recommends using disks of the same size for SAP HANA.