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I am repeating myself here (and in the same month!), so I apologize, but it was a different thread, so in case this helps clarify the Realtek discussion, this is an excerpt from /sys/pci/if_rl.c (the c file for the Realtek driver by the author of the driver for FreeBSD). He actually states that : "This is probably the worst PCI ethernet controller ever made, with the possible exception of the FEAST chip made by SMC", so defend the chip if you like but I think that says it all, and from a person who knows a lot more than I do about good vs. bad network chips: /* * 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. */ Jeff Aaron with Morad wrote: >> I have dozens of m0n0walls and full-blown servers with RealTek cards >> and, while I *always* recommend Intel NICs, the RTL8139s that come with >> the motherboards sometimes have actually done pretty well when hooked up >> to internet connections, wifi APs, etc. >> > > >> Lee Sharp wrote: >> >>> From: "Aaron with Morad" <aaronc at morad dot ab dot ca> >>> >>> >>>> "the Realtek cards sucks!" >>>> >>>> Haha... I agree. >>>> >>> While we are testifying about hardware... :-) I have at least 25 >>> Realtek cards in production on m0n0wall with no problems. They are >>> slow, but not as slow as the internet connection. However, I am >>> running them all in well ventilated cases, and with good power >>> supplies. Heat and bad power supplies cause more problems than >>> realtek nics. >>> > > With all of this I must confess, I do have three other m0n0walls running > Realtek NICs just fine - these other m0n0walls serve other routing purposes > in our network. It just seems to be the two units for the ISP side of our > business that have given me trouble (one operational and the other a > warm-standby). These would be the heaviest used out of the bunch. I > suppose I should have changed out the memory and CF card in the process of > elimination but with all of the talk (before this thread) regarding the > performance of the Realtek NICs I thought it would be easier to complain > (haha, sorry) and change out the box for an Intel config. The units I > pulled out will still be used, perhaps with new RAM and CF cards this time, > and maybe somewhere less critical to start with... > > > > Aaron > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: m0n0wall dash unsubscribe at lists dot m0n0 dot ch > For additional commands, e-mail: m0n0wall dash help at lists dot m0n0 dot ch > > > |