HP Z230 User Manual

Software RAID solution
This section summarizes software RAID considerations that are specific to the Linux environment,
and provides links to additional configuration resources.
Software RAID considerations
The Linux kernel software RAID driver (called md , for multiple device ) offers integrated software RAID
without the need for additional hardware disk controllers or kernel patches. Unlike most hardware
RAID solutions, software RAID can be used with all types of disk technologies, including SATA, SCSI,
and solid-state drives. This software solution requires only minimal setup of the disks themselves.
However, when compared to hardware-based RAID, software RAID has disadvantages in managing
the disks, breaking up data as necessary, and managing parity data. The CPU must assume some
extra loading: disk-intensive workloads result in roughly double the CPU overhead (for example, from
15% to 30%). For most applications, this overhead is easily handled by excess headroom in the
processors. But for some applications where disk and CPU performance are very well balanced and
already near bottleneck levels, this additional CPU overhead can become troublesome.
Hardware RAID offers advantages because of its large hardware cache and the capability for better
scheduling of operations in parallel. However, software RAID offers more flexibility for disk and disk
controller setup. Additionally, hardware RAID requires that a failed RAID controller must be replaced
with an identical model to avoid data loss, whereas software RAID imposes no such requirements.
Some software RAID schemes offer data protection through mirroring (copying the data to multiple
disks in case one disk fails) or parity data (checksums that allow error detection and limited rebuilding
of data in case of a failure). For all software RAID solutions on HP workstations, redundancy can be
restored only after the system is shut down so that the failed drive can be replaced. This replacement
requires only a minimum amount of work.
Performance considerations
Disk I/O bandwidth is typically limited by the system bus speeds, the disk controller, and the disks
themselves. The balance of these hardware limitations, as affected by the software configuration,
determines the location of the any bottleneck is in the system.
Several RAID levels offer improved performance relative to stand-alone disk performance. If disk
throughput is restricted because of a single disk controller, RAID can probably do little to improve
performance until another controller is added. Conversely, if raw disk performance is the bottleneck, a
tuned software RAID solution can dramatically improve the throughput. The slower disk performance
is, relative to the rest of the system, the better RAID performance will scale, because the slowest
piece of the performance pipeline is being directly addressed by moving to RAID.
Configuring software RAID
See the following sites for additional information about configuring software RAID on Red Hat
Enterprise Linux (RHEL) or SUSE Linux Enterprise Desktop (SLED):
●
Red Hat Enterprise Linux 6—See the
Storage Administration Guide at http://docs.redhat.com/
docs/en-US/Red_Hat_Enterprise_Linux/6/html/Storage_Administration_Guide/index.html
●
Red Hat Enterprise Linux 5—See the
Deployment Guide at http://docs.redhat.com/docs/en-US/
Red_Hat_Enterprise_Linux/5/html/Deployment_Guide/ch-raid.html.
●
SLED 11—See the
Deployment Guide at http://www.suse.com/documentation/sled11/
book_sle_deployment/?page=/documentation/sled11/book_sle_deployment/data/
book_sle_deployment.html.
112 Appendix B Configuring RAID devices

HP Z230 Specifications

General

Product type	Workstation
Motherboard chipset	Intel® C226
ECC	Yes
Memory slots	4x DIMM
Internal memory	4 GB
Memory channels	Dual-channel
Memory clock speed	1600 MHz
Internal memory type	DDR3-SDRAM
Maximum internal memory	32 GB
Memory layout (slots x size)	1 x 4 GB
Chassis type	Desktop
Product color	Black
Country of origin	China
Placement supported	Vertical
Number of 3.5\" bays	1
Water cooling system	No
HDD speed	7200 RPM
RAID levels	0, 1
HDD interface	SATA
Storage media	HDD
Optical drive type	DVD Super Multi
Total storage capacity	500 GB
PS/2 ports quantity	2
DisplayPorts quantity	3
Serial ports quantity	-
USB 2.0 ports quantity	6
VGA (D-Sub) ports quantity	0
USB 3.2 Gen 1 (3.1 Gen 1) Type-A ports quantity	4
Ethernet LAN data rates	10, 100, 1000 Mbit/s
On-board graphics card ID	0x412
Discrete graphics card model	Not available
On-board graphics card model	Intel® HD Graphics 4600
Maximum on-board graphics card memory	1.74 GB
On-board graphics card base frequency	350 MHz
On-board graphics card DirectX version	11.1
On-board graphics card dynamic frequency (max)	1150 MHz
Power supply	240 W
Tcase	72.72 °C
Bus type	DMI2
Stepping	C0
Processor cache	6 MB
Processor model	i5-4570
System bus rate	5 GT/s
Processor family	Intel® Core™ i5
Processor socket	LGA 1150 (Socket H3)
Processor codename	Haswell
Processor frequency	3.2 GHz
Processor cache type	Smart Cache
Processor lithography	28 nm
Processor manufacturer	Intel
Processor front side bus	- MHz
PCI Express slots version	3.0
Processor boost frequency	3.6 GHz
Processor operating modes	64-bit
PCI Express configurations	1x16, 2x8, 1x8+2x4
Thermal Design Power (TDP)	84 W
Maximum number of PCI Express lanes	16
Memory clock speeds supported by processor	1333, 1600 MHz
Memory bandwidth supported by processor (max)	25.6 GB/s
Operating system installed	Windows 7 Professional
Scalability	1S
Processor code	SR14E
Processor ARK ID	75043
Intel TSX-NI version	0.00
Processor package size	37.5 x 37.5 mm
Graphics & IMC lithography	22 nm
Supported instruction sets	AVX 2.0, SSE4.1, SSE4.2
Thermal solution specification	PCG 2013D
Intel Identity Protection Technology version	1.00

Weight and Dimensions

Depth	384 mm
Width	337 mm
Height	100 mm
Weight	7200 g