Hi,
I did some tests over my network and got strange results. First, I verified that everything is correctly connected, and that theorical rates are reached (Giga), using two Asus P9X79. The two computers have RAID10 drives : no HDD bottleneck. I used only one of the two Ethernet ports (no support for double connection with the switches).
Transfer rates are ok : 110-120MB/s.
Then I built another machine, using old parts.
mobo : Asrock N68-VS3-FX : NForce 630a chipset. I tried different setups, from single IDE HDD to SATA RAID10, with nearly the same results. All useless hardware is disabled, including the onboard Ethernet adapter : replaced with a PCI Giga adapter : SysKonnect SK-9521 v2.0. Jumbo frames enabled everywhere.
I got not too bad transfer rates from the Asrock to the P9X79 ; CPU usage 25%, networlk usage : 30%. I think that the PCI bus is the bottleneck : LAN + HDD transfers = bus saturation. Same results with IDE or SATA or SATA RAID.
Results with transfer from Asrock to P9X79 :
Then, from the P9X79 to the Asrock : very bad transfer rate ! I can't explain, and any advice is welcome !
The Asrock is intended for downloading, and D/L files have to go to the NAS (a low end model). (28MB/s is normal for this NAS).
Then I tested from the Asrock to the NAS, and got an incredible 13.5MB/s !
The last test... On the P9X79, I initiated file transfers from the Asrock to the NAS, with Explorer and shared directories. As a result, files go from the Asrock to the P9X79, and from the P9X79 to the NAS. These transfers can easily be seen with the network monitor on the P9X79 : 50% of the NIC bandwidth = 56MB/s (28MB/s+28MB/s, duplex).
Now I get nominal transfer rate ! I absolutely don't understand why ! Any advice is more than welcome !
As you can see, the only way to get nominal write speed on the NAS is to initiate transfers on the workstation. I'd like to understand, and I'd prefer to launch transfers from Remote Desktop, and then let the devices speaking together...
Asrock to NAS : only 50%. Asrock -> P9X79 -> NAS : 100%.
Weird, is'nt it ?