Raid5 Help Wanted, Slow Speeds

[kittkitan]

Today parts finally arrived for me to mess around with 4gb networking, and the results have largely been great

except for one issue

I am Using RAID5 (3x1tb drives), just some drives i had laying around since i can't afford the drives i want yet

Downloading from the NAS is great, as you can see with my downloads file(attached picture) the 1.6gb file i had laying around FLEW

uploading is a different story, it starts great, but halfway it drops down to 20MB/s, (attached picture)

-i do know raid5 has slower write speeds but i wasn't expecting sudden drops

 

I am using the Intel onboard raid controller, i have heard this could be an issue

but before i fork out money on a raid-card, i figure i'd ask the community, especially if a workaround can be suggested or advised

 

The drives in raid are 2X WD greens and a Seagate drive

as said, i used ones that were laying around cause i wanted to test things before getting some better NAS drives

 

so any help is appriciated

[Eniqmatic]

What is the full specs of the NAS/machine that you are copying to and from?

[kittkitan]

NAS:

CPU i7-3820@3.6ghz
8gb ram DDR3

670GTX graphics

p9x79-motherboard
120gb SSD (boot drive)
And the before mentioned three drives in raid5

 

Main Computer:

CPU: AMD 4.0ghz octocore

ram: 32gb

1060GTX + 6gb Vram

2x HyperX 240gb SSD (Raid0)(boot drive)

 

I have tried other computers, and even copying files on the computer itself
Anything Writing to that Raid Seems to just drop to 20mb/s halfway
while Reads are fantastic, even on a 1gb connection (120MB/s)

[kittkitan]

=w= update, i am not getting weird speeds reading and writing,

i think one or more of the drives have failed

 

will keep updated, while i try to find some better drives to make a raid with

[Eniqmatic]

I would try the tests the other way round, I.E use the NAS machine to read and write from the desktop. Should help you narrow it down a bit but you say you might have found the issue already so!

[Falconevo]

Check the S.M.A.R.T information on each of the drives to check its health, sounds like one is misbehaving.

[Electronics Wizardy]

2 hours ago, kittkitan said:

=w= update, i am not getting weird speeds reading and writing,

i think one or more of the drives have failed

 

will keep updated, while i try to find some better drives to make a raid with

Don't use the onboard raid card, use storage space on windows or a hardware raid card like a h700 or something from lsi.

 

 

[kittkitan]

that is a future plan, problem is expense

 

feel free to suggest some cheap cards,

[Falconevo]

19 hours ago, Electronics Wizardy said:

Don't use the onboard raid card, use storage space on windows or a hardware raid card like a h700 or something from lsi.

 

 

Storage spaces ideally should be using pass-through AHCI based HBA controller.

 

Would probably look for a Dell H330 so it can be used in HBA/AHCI mode instead of being utilised as a RAID HBA.  That way you can utilise JBOD style disk layouts in storage spaces and have support for storage spaces direct.

[kittkitan]

Welll i found out after hunting, i could get the Intel Rapid Storage Application, and messed around  with settings

 

turning on writeback, and using an SSD as "acceleration" 

I now get 450MB/s Read and Write Over my network! 

 

Still tweaking settings, but now its useable!

 

I still am looking for a raid-card cause the Intel raid software doesn't seem to be quite as good as a dedicated card, but in the short term, it will do

 

 

Thanks a lot for all your help!

[Falconevo]

Write back is always helpful, however it is generally disabled when a BBU (Battery Backup Unit) is not available as a loss in power will cause data in that cache to be lost, permanently.. not usually a big deal in residential stuff but in servers it is.

 

The SSD is essentially becoming a Layer2 IO cache and will cache all the reads and writes on the volume you have created.  This is masking the actual performance of the array underneath it, the information will be slowly dumped to the mechanical disks over time.

 

As long as you are happy though, some RAID cards can utilise a layer2 SSD for cache also.  Do yourself a favour and keep an eye on the wear level of the SSD while in this mode, an SSD will start misbehaving when it starts to get close to its maximum wear level (total TB written).  Check the S.M.A.R.T information on the SSD every few months.