RAID50 slow write speed

Question

Initial Configuration:

RAID:

• Disk Drives: 6 HDD TOSHIBA MBF2600RC (600 Gb, 16 Mb, 10025 RPM, SAS, 600 Mb/s)

• 2 Spans

• Motherboard: SuperMicro X8DTU-6F+/6TF

• RAID Controller: SuperMicro SMC2108

• Virtual Group: RAID50

• Polices:

  • Access: RW
  • Read: Normal
  • Disk Cache: Enable
  • I/O: Cached
  • Disable BGI: NO
  • Default Write: Write Through

Used Operation System: Windows Server 2016

Result:

CrystalDiskMark Metrics:

Read [MB/s]: 221.5

Write [MB/s]: 38.30

Ubuntu Live CD Metrics:

Read [MB/s]: 270.1

Write [MB/s]: 49.5

Question:

What can I attempt to increase Write Speed?

Should I reconfigure RAID50 settings, or configure different type of RAID?

Answer 1

Changing Default Write policy to 'WRITE ALWAYS BACK' has aligned rate of speed:

Read [MB/s]: 222.6

Write [MB/s]: 208.8

So it's a good practice to consider this option for write intensive tasks.