Netgear FA311 10/100 PCI - Only 400kbs

[Mike NustBe]

First time post...

My existing network only got 1mps so I decided to switch it out. I found a netgear FA311 for cheap and picked it up and switched it out. Now I am getting half the speed. An average of 400kbs. Very slow. Do I need to install the drivers or something?

 

[Ericloewe]

From the rl driver source, which runs the Realtek 8139 Ethernet transceiver present on your card:

Code:

/*
* RealTek 8129/8139 PCI NIC driver
*
* Supports several extremely cheap PCI 10/100 adapters based on
* the RealTek chipset. Datasheets can be obtained from
* www.realtek.com.tw.
*
* Written by Bill Paul <wpaul@ctr.columbia.edu>
* Electrical Engineering Department
* Columbia University, New York City
*/

/*
* The RealTek 8139 PCI NIC redefines the meaning of 'low end.' This is
* probably the worst PCI ethernet controller ever made, with the possible
* exception of the FEAST chip made by SMC. The 8139 supports bus-master
* DMA, but it has a terrible interface that nullifies any performance
* gains that bus-master DMA usually offers.
*
* For transmission, the chip offers a series of four TX descriptor
* registers. Each transmit frame must be in a contiguous buffer, aligned
* on a longword (32-bit) boundary. This means we almost always have to
* do mbuf copies in order to transmit a frame, except in the unlikely
* case where a) the packet fits into a single mbuf, and b) the packet
* is 32-bit aligned within the mbuf's data area. The presence of only
* four descriptor registers means that we can never have more than four
* packets queued for transmission at any one time.
*
* Reception is not much better. The driver has to allocate a single large
* buffer area (up to 64K in size) into which the chip will DMA received
* frames. Because we don't know where within this region received packets
* will begin or end, we have no choice but to copy data from the buffer
* area into mbufs in order to pass the packets up to the higher protocol
* levels.
*
* It's impossible given this rotten design to really achieve decent
* performance at 100Mbps, unless you happen to have a 400Mhz PII or
* some equally overmuscled CPU to drive it.
*
* On the bright side, the 8139 does have a built-in PHY, although
* rather than using an MDIO serial interface like most other NICs, the
* PHY registers are directly accessible through the 8139's register
* space. The 8139 supports autonegotiation, as well as a 64-bit multicast
* filter.
*
* The 8129 chip is an older version of the 8139 that uses an external PHY
* chip. The 8129 has a serial MDIO interface for accessing the MII where
* the 8139 lets you directly access the on-board PHY registers. We need
* to select which interface to use depending on the chip type.
*/

tl;dr: Those things are not worth the silicon they're made of and should be avoided at all costs.

I'm not sure I dare to ask what the remaining hardware is...

 

[Mike NustBe]

I stuck a TB in an old dell 4600 for a NAS with existing hardware. FreeNAS was a nice addition to my budget NAS. I cant believe this card is advertised as 10/100 Mpbs.... Which is obviously complete BS.

 

[Mike NustBe]

Could someone recommend a decent budget PCI NIC?

 

[jgreco]

$35 for an Intel desktop Ethernet card gets you high end performance and problem-free operation.

 

[jgreco]

http://m.newegg.com/Product/index?itemnumber=N82E16833106036

 

[cyberjock]

Welcome to the world where the world lies to you regularly and you probably aren't spending the time to do the research. Don't feel bad, we've all been duped before waking up and realizing how fractured the world is with putting out quality hardware.

 

[cyberjock]

Keep in mind that PCI will *never* fully saturate Gb LAN. The PCI bus can't move data at the required speeds. ;)

 

[Mike NustBe]

Thanks for replies all...

 

[jgreco]

Keep in mind that PCI will *never* fully saturate Gb LAN. The PCI bus can't move data at the required speeds. ;)

Don't be silly. Going all the way back to the advent of PCI in 1992, where the bus speed was 33 MHz at 32 bits, you get a potential throughput of 133MB/sec, which is almost adequate to fully saturate gigE unidirectionally. In practice there's a fair bit of overhead but it is far more than the "Realtek" ("Badjunk" IMO) chip can cram out.

More current implementations support 66 MHz at 64 bit, for 533MB/sec, and PCI-X extends that into variants supporting up to about 4GB/sec. I've got several quad gigE PCI-X cards that can definitely saturate all the ports. The PCI-X stuff is mostly available on server boards though, and of course you have to sort through the quagmire of what your card and the PCI bus supports to see what your limit is.

Still, for a NAS, there is no reason that a home user shouldn't be able to get a satisfactory result from a quality PCI ethernet card like the Intel PWLA's.

Now if you want to take a shot at Realtek, be my guest. To get saturation of gigE, you need a high quality, no compromises ethernet card. That's true whether we're talking PCI, PCI-X, or PCIe.