Slow transfer speed

[Stefan]

Hi everyone,

This has probably been asked a million times but please hear me out. I'm a .net software developer and my knowledge of everything not-Microsoft is simply shocking ;)

I'm trying to get a NAS going at home and thus far the process has been fairly painless due to the amount of work everyone has put into FreeNAS. The problem that I'm experiencing at the moment though it that my transfer speeds seems a bit slow.

I currently have a NAS box which a friend set up for me using CentOs + mdadm which works great but I would love to have something I can manage myself without learning an entire new platform. As mentioned my Linux knowledge is pathetic....

I installed FreeNAS on a second PC with basically the same specs as my current (Linux) NAS. The problem I'm having though it that the copy speed seems a bit slow:

(I did not use any tool for these stats, just rough averages as reported by Windows while copying a 2GB file)

Linux NAS - Up: 58MB/s, Down: 62MB/s
FreeNas - Up: 28MB/s, Down: 35MB/s

Both NAS boxes have 3x 2TB 7200RPM drives and I'm sure I left out a LOT of details, please feel free to ask.

Some extra info, I'm accessing the share using a Windows (CIFS) Share in FreeNas. I played around with iscsi as a test and that seems to be a lot faster. The same 2GB file copies to the share in less than 10 seconds and when I copy it back to my machine it takes about 40 seconds (starts out slow and gradually increases in speed, as reported by windows).

I also doubled the memory in the machine and that made no difference. I started out with 2GB (I somehow thought I added 2x 2GB modules but they were 1GB modules) and then changed it to 4GB (2x 2GB modules).

Googling yielded a lot of complicated concepts and possible solutions so I would appreciate it if someone can just point me to something simple to determine where the bottleneck is (or any other ideas). I dont think its my drives as the ISCSI setup had some good results.

Please feel free to correct me on any incorrect assumption I have made. I'm a complete noob when it comes to this type of thing.

 

[Scareh]

from the guidelines:

The more RAM, the better the performance, and the FreeNAS® Forums provide anecdotal evidence from users on how much performance is gained by adding more RAM. For systems with large disk capacity (greater than 8 TB), a general rule of thumb is 1 GB of RAM for every 1 TB of storage.
aka the more the merrier ;)
since i know it'll be question later on: what kinda of NIC are you using? intel/realtek?

 

[cyberjock]

Yeah, the FreeNAS manual currently recommends 8GB of RAM minimum and more is always better.

What's the CPUs in both machines and what hard drive configuration did you use(UFS, ZFS). If ZFS, what was your zpool design.

I don't believe centOS supports ZFS. If it doesn't and you are using ZFS your speed comparisons aren't apples-to-apples.

iSCSI on ZFS isn't generally recommended. There are major performance issues over the long-term.

 

[Stefan]

Thanks for the replies :)

I think since I have less memory than the recommended I should probably address that before trying anything else. Thanks for pointing me in the right directions.

I'll revert back shortly with the results, both CPUs are really low end Core2Duos - will have to check the exact details.