ReadyNAS Pro 2 Slow write speeds

[cory7761]

Hello everyone. I hope someone on here can help me.  I'll try to keep this short. I bought my Readynas Pro 2 about 5 years ago. It was the diskless model. I put 2 7200rpm 3TB seagate drives in it. I always got pretty fast sequential read and write speeds (90-100MBps). About a year ago, one of the drives started to fail so I replaced it with a WD 3TB Red hard drive. Since then, my read speed is still fast (over 100MBps), but my write speed is all over the place.  It will usually start out at 40MBps the quickly drop to around 20MBps and fluctuate between 20 and 30 the reast of the way.  These are large, single file, sequential writes. 

I live with it for awhile then I started wondering if it was because of the different platter speeds in the drives. Seagate is 7200rpm, WD Red is ~5400rpm.  I bought a second WD Red and installed it in place of the seagate and nothing changed.  I have tested the speed of the WD Red drives by themselves in a separate computer and they write at over 130MBps. I am using the default proprietary Netgear raid, I think it's called X-Raid. 

If anyone has any ideas or suggestions, I would really appreciate it. Thank you for your time.

Cory

[StephenB]

It's not the mismatch in the drive RPM (as you have already concluded).

Are you using both ethernet connections or just one?  How full is the disk volume?  what firmware are you running?

It would be good to try a direct-connect test (directly connecting the NAS to your PC NIC card).  You need to temporarly assign a static IP to the NAS.

-If the pro is using DHCP, then it will use 192.168.168.168 during the direct connect

-set the PC to 192.168.168.100 with subnet mask 255.255.255.255

-access the nas via \\192.168.168.168 (not by name).

NAStester is a convenient tool for testing speeds: http://www.808.dk/?code-csharp-nas-performance

[cory7761]

I am only using one ethernet connection but that is what I have always done. The disks are 51% full. Firmware version RAIDiator 4.2.28.  I will try the direct connect when I get home if you think it will be beneficial. If I can read at over 100MBps then I should theoretically be able to write that fast. Right? Right now I have a router and a switch between my computer and the NAS. Everything is hard wired and all ports are gigabit. 

Thank you for your help.

Cory

[StephenB]

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@cory7761 wrote:

I am only using one ethernet connection but that is what I have always done. The disks are 51% full. Firmware version RAIDiator 4.2.28.

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Good.  That rules out any issues due to nic bonding and volume fragmentation.

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@cory7761 wrote:

 If I can read at over 100MBps then I should theoretically be able to write that fast. Right?

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Writes are inherently slower - the data needs to be written to both disks.  Though the difference should be slight.  Smallnetbuilder's performance tests are here: http://www.smallnetbuilder.com/nas/nas-reviews/31471-new-to-the-charts-netgear-readynas-pro-2?showal...

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@cory7761 wrote:

Right? Right now I have a router and a switch between my computer and the NAS. Everything is hard wired and all ports are gigabit. 

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That's useful to know.  The direct-connect will let us know if the router, switch, or cabling between them are slowing down the writes (or not).