[HiDefDon]

I am currently setting up 3 PCs with Gigabit ethernet where one of the PCs is configured as the network file server. The network file server PC has an on-board GigaBit network controller but I recently discovered that the motherboard has a defect which limits network speed to 100Mb/sec. I know this because one of the other PCs has the same motherboard and it works fine at 1Gb/sec. Rather than tear the whole PC apart to replace the motherboard, I purchased two Intel GigaBit NICs and was planning to install these NIC cards in the 2 PCs which do not have Gigabit capability. I have also verified that all PC network interfaces and my network switch do support "jumbo frames".


Additional information...

1) Hard disks on the file server are all parallel ATA Seagate drives.

2) For HDTV recording and playback I will be reading and writing data to the file server at an average rate of 19.4Mb/sec.

3) There will be at most three simultaneous transport streams being written or read at the file server.


Questions... With this configuration, how much bandwidth or performance do I lose by using the PCI network interface card rather than a direct on-motherboard network interface? What is the overall impact/limitation of PATA hard drive performace? Will there be sufficient bandwidth at the file server to edit transport streams (i.e. disk-to-disk copy as quickly as possible) while the file server PC is handling data streams fro the other 2 PCs?


Thanks.

DonP

 

[Brian Pickering]

The onboard chips are probably just hanging off the same PCI bus that the addon card will be. Only a few of the newer chipsets, like the high end intel and nvidia ones have a direct pipe to the LAN chip. You probably won't see much difference.


I know on my own gigabit network with file server and a few PCs I transfer from, I get between 25 and 30 MiBytes/sec, which is pretty much the limit of the HDs that are being written to. Two of the Gb chips are the aforementioned nvidia onboard, and one is a PCI intel, and there is virtually no difference in speed between the two.

 

[ilee01]

Your network file server PC... JBOD or any raid set up for your PATA disks? I've built a file server like this: ASUS M2NPV-VM (NV Raid 5 =4x400 SATA II), gigabit NIC, gigabit switch w/jumbo frame. Since it is not as fast as my another PC w raid 0 (2x250 PATA) setup for writes but read/access seemed on par. I get ~24 (raid 0) and ~22( raid 5) mb/sec for writing 1.4 gb movie data but an average 35 mb/sec for streaming contents.

 

[Brian Pickering]

It's a Linux software RAID setup, with a combination of 6x120GB and 6x500GB drives mixed SATA and PATA from what I've gotten over the years. Since the drives aren't identical, its pretty much limited by the speed of the slowest drive. Also, the systems I'm reading/writing from only have one HD, so thats probably most of the limiting factor.