Problem: 7200RPM slower than 5400RPM in RAID 0 setup

[citizen_kane]

Hello. I have a couple of Sharkoon Raid 5-bay RAID Stations running a RAID0 configuration with four 4TB WD Red disks (5400RPM). I recently purchased a third cabinet, and decided to go with four 4TB WD Red Pro (7200RPM) disks to increase performance.

I was surprised to discover that the Red Pro setup performed worse than the WD Red basic setup. I also tried running WD Black disks (7200RPM) to see if the problem persisted, which it did. The output of my application (EVS HDSDI Video Ingest software) was significantly worse in the 7200RPM setup, and my ATTO benchmark tests confirmed this:

5400RPM:

7200RPM:

The 5400RPM setup managed write speed of 170MB/s, whereas the 7200RPM setup only delivered a write speed slightly above 100MB/s. The reading speed however was somewhat improved on the 7200RPM setup. Whether or not I used USB3.0 or eSata made no difference.

Has anyone ever encountered this? Is there a logical explanation, or something to be done to increase performance of the 7200RPM setup?

Espen, Norway

 

[helpstar]

firmware of the station is up to date?

 

[citizen_kane]

firmware of the station is up to date?

The station is brand new, so I would think so. Have to double check next week.

 

[helpstar]

couldn´t find new firmware

but could be the HDD´s normal performance:
https://www.pcper.com/reviews/Storage/Western-Digital-6TB-Black-and-6TB-Red-Pro-Review-Bigger-and-Faster/Sequential-Perfor

which HDDs exactly are you using?
e.g. wd40efrx

 

[marko55]

Did you give the RAID array a chance to initialize? You probably cannot see it happening but right after you create a parity RAID array the controller in that thing may quickly initialize the volume so you have access to the storage but it still needs to perform a full background initialization to verify the consistency across all disks and during that time your performance isn't gonna be great; especially on writes.

Depending on the performance of the controller in that thing, with 4TB drives, that could take at least 4 hours. For reference, if this were on an Intel mobo using chipset RAID it would take almost 2 days. On a proper enterprise RAID controller it could finish in just a few hours.

After that's done there's NO reason the faster 7200RPM drives shouldn't be faster.

 

[citizen_kane]

couldn´t find new firmware

but could be the HDD´s normal performance:
https://www.pcper.com/reviews/Storage/Western-Digital-6TB-Black-and-6TB-Red-Pro-Review-Bigger-and-Faster/Sequential-Perfor

which HDDs exactly are you using?
e.g. wd40efrx

Not sure, have to check on wednesday.

 

[citizen_kane]

Did you give the RAID array a chance to initialize? You probably cannot see it happening but right after you create a parity RAID array the controller in that thing may quickly initialize the volume so you have access to the storage but it still needs to perform a full background initialization to verify the consistency across all disks and during that time your performance isn't gonna be great; especially on writes.

Depending on the performance of the controller in that thing, with 4TB drives, that could take at least 4 hours. For reference, if this were on an Intel mobo using chipset RAID it would take almost 2 days. On a proper enterprise RAID controller it could finish in just a few hours.

After that's done there's NO reason the faster 7200RPM drives shouldn't be faster.

Great suggestion! I will try to rebuild the RAID on wednesday and let it stand idle for a day before trying again.

Espen

 

[marko55]

Did you give the RAID array a chance to initialize? You probably cannot see it happening but right after you create a parity RAID array the controller in that thing may quickly initialize the volume so you have access to the storage but it still needs to perform a full background initialization to verify the consistency across all disks and during that time your performance isn't gonna be great; especially on writes.

Depending on the performance of the controller in that thing, with 4TB drives, that could take at least 4 hours. For reference, if this were on an Intel mobo using chipset RAID it would take almost 2 days. On a proper enterprise RAID controller it could finish in just a few hours.

After that's done there's NO reason the faster 7200RPM drives shouldn't be faster.

Great suggestion! I will try to rebuild the RAID on wednesday and let it stand idle for a day before trying again.

Espen

So I just realized you're running RAID-0, which doesn't do what I'm talking about. That would only be if you were using parity RAID like 5 or 6. My mistake. Very sorry.

 

[citizen_kane]

Did you give the RAID array a chance to initialize? You probably cannot see it happening but right after you create a parity RAID array the controller in that thing may quickly initialize the volume so you have access to the storage but it still needs to perform a full background initialization to verify the consistency across all disks and during that time your performance isn't gonna be great; especially on writes.

Depending on the performance of the controller in that thing, with 4TB drives, that could take at least 4 hours. For reference, if this were on an Intel mobo using chipset RAID it would take almost 2 days. On a proper enterprise RAID controller it could finish in just a few hours.

After that's done there's NO reason the faster 7200RPM drives shouldn't be faster.

Great suggestion! I will try to rebuild the RAID on wednesday and let it stand idle for a day before trying again.

Espen

So I just realized you're running RAID-0, which doesn't do what I'm talking about. That would only be if you were using parity RAID like 5 or 6. My mistake. Very sorry.

OK, no worries. Back to the drawing board. Thanks anyway

 

[citizen_kane]

couldn´t find new firmware

but could be the HDD´s normal performance:
https://www.pcper.com/reviews/Storage/Western-Digital-6TB-Black-and-6TB-Red-Pro-Review-Bigger-and-Faster/Sequential-Perfor

which HDDs exactly are you using?
e.g. wd40efrx

The WD Red Pros are WD4002FFWX, the WD Blacks are WD4004FZWX.

 

[citizen_kane]

I have done some more research on this.

After formatting the partitions with allocation unit size 64K, as opposed to default, I get better results on the WD Red Pro and WD Black setups compared to the WD Red. As expected.

Red Pro

Black

Red

However, the output of my application still performs significantly worse on the 7200RPM setups compared to the 5400RPM setup. I am beginning to suspect that the Raid Stations aren't responsive enough to handle the load on the 7200RPM disks, and thus slows down to process all the information. I imagine this maybe not being visible in disk tests because the payload test is done more rapidly that actual file creation over time. Does that make sense?

Espen, Norway.