slow network speed for raid5 freenas

[cuti7399]

Here is my system spec: (little overkill but i'm just trying it out)
P5W deluxe with gigabit interenet port
E6600 cpu (stock right now)
2x1gb ddr2 800
4.3ghz hdd with FreeNAS on it
3x320 seagate 7200.10 drives in software raid5 created by FreeNAS

Anyway, it seem that this configuration is on the same speed with my old 10/100 simpletech NAS. But i like FreeNAS because there are so much more to configure.

So:

What am I doing wrong?
Should I get a dedicated raid card? if so, would it be any faster than the Dlink DNS-323 (something i'm looking at)

Thanks for any help.

 

[Madwand1]

Originally posted by: cuti7399
What am I doing wrong?
Should I get a dedicated raid card? if so, would it be any faster than the Dlink DNS-323

Unless you're not using gigabit end-to-end, it's not your hardware. Look into write caching options in FreeNAS, or consider using Intel's RAID implementation -- it can certainly run much faster than most if not any consumer NAS box.

 

[Crusty]

Raid 5 on 3 of those drives won't be able to max out a gigabit network.

What kind of transfer speeds are you actually seeing?

 

[Madwand1]

Depending on the vintage of the 7200.10, you can get somewhere around 80 MB/s sustained maximum, 65 MB/s average, and 40 MB/s minimum, per drive.

An ideal 3-drive RAID 5 implementation would give you 2x that, coming in at 160 MB/s, 130 MB/s, and 80 MB/s respectively. So at minimum, it's correct that this setup cannot fill a gigabit pipe, but it can on average and at maximum in an ideal setup. The general point is that it can exceed it under ideal conditions, and otherwise come close in theory.

The following graph has some actual data from a 3-drive on-board RAID 5 setup. This setup probably hit the best parts of the drives, which IIRC were all Maxtor DM10's, which are a bit slower in sustained transfers than the 7200.10.

http://i89.photobucket.com/alb...-3vs4-wb-on-vs-off.png

Bottom line -- while it's correct to think that those drives in 3-drive RAID 5 cannot always maximize gigabit, they can approach it, and should in theory be able to contribute towards pretty decent gigabit transfer numbers.

However, when theory meets OS and file transfer protocol limitations, it's generally not pretty...

 

[cuti7399]

Update: moving 20gb of files would take about ~2hrs which is about the same as the NAS

what program do I use the measure the i/o speed?
how do I use the intel raid5? because when I setup in intel raid5, FreeNAS does not recognize these as raid5 but only see them as individual drive.

Thanks again

 

[Madwand1]

ATTO is a quick & dirty file-system level sequential read/write benching tool.

You can find it through here:

http://kb.ciprico.com/lore/article.php?id=268

Here are some of my setup parameters and results for example:

http://i89.photobucket.com/alb...tto-random-network.png

One sure way to run Intel RAID 5 would using a Windows OS, where the drivers and utility work for sure. I don't know if it's possible or recommended within FreeNAS -- you'd have to find supporting drivers for that. You'd probably be better off researching FreeNAS's RAID 5 implementation instead, notably for write caching. Write performance issues should show up in the ATTO results.

Note that getting an add-on card would have similar issues -- you'd have to find out about support specific for FreeNAS or its base OS.