We help IT Professionals succeed at work.

RAID50 slow speed

Last Modified: 2018-12-19
My Problem is RAID50 slow speed.

Initial RAID Configuration:

  • 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:
    1. Access: RW
    2. Read: Normal
    3. Disk Cache: Enable
    4. I/O: Cached
    5. Disable BGI: NO
    6. Default Write: Write Through
    7. Used Operation System: Windows Server 2016


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

What can I attempt to increase Write Speed?
Should I reconfigure RAID50 settings, or configure different type of RAID?
Watch Question

Jose Gabriel Ortega CastroTop-Rated Plus Freelancer (Upwork)/EE Solution Guide / CEO / Photographer
Awarded 2018
Distinguished Expert 2018

What if you try a RAID 10 (raid 1 + raid 0), you can do this in pair number of disks.


Is it a guarantee of speed increasing?
Jose Gabriel Ortega CastroTop-Rated Plus Freelancer (Upwork)/EE Solution Guide / CEO / Photographer
Awarded 2018
Distinguished Expert 2018

Use a calculator to determine the speeds
Distinguished Expert 2018
This problem has been solved!
(Unlock this solution with a 7-day Free Trial)
Distinguished Expert 2019

Hardly surprising it is slow, write-through cache due to lack of battery backup, you could turn write-back caching on, it is a gamble with the data but not so much as turning the disk cache on !

RAID 6 would make more sense than RAID 50 with so few disks, it's only when you get to several (about 7) disks that you need nested RAID. If you can spare the space RAID 10 would be much faster since it does not need 4 I/Os to perform one write.
kevinhsiehNetwork Engineer

RAID 50 for this configuration makes no sense. If you want best performance, use RAID 10. Best write and read speed. If you want more capacity at the expense of write speed, use RAID 5. Nothing else makes sense.

Note that normally RAID 5 isn't viable anymore due to large capacity disks with 10-15 UBR rates. However, since you're using smaller enterprise disks of a limited number, it is okay to use RAID 5 like it's 2008.

If you were using drives over 1 TB, the rule of thumb is RAID 10 or 6. If you had a really large number of drives, I would consider also RAID 60.

Gain unlimited access to on-demand training courses with an Experts Exchange subscription.

Get Access
Why Experts Exchange?

Experts Exchange always has the answer, or at the least points me in the correct direction! It is like having another employee that is extremely experienced.

Jim Murphy
Programmer at Smart IT Solutions

When asked, what has been your best career decision?

Deciding to stick with EE.

Mohamed Asif
Technical Department Head

Being involved with EE helped me to grow personally and professionally.

Carl Webster
CTP, Sr Infrastructure Consultant
Empower Your Career
Did You Know?

We've partnered with two important charities to provide clean water and computer science education to those who need it most. READ MORE

Ask ANY Question

Connect with Certified Experts to gain insight and support on specific technology challenges including:

  • Troubleshooting
  • Research
  • Professional Opinions