----- Original Message ---- > From: John R Pierce <pierce at hogranch.com> > To: centos at centos.org > Sent: Tue, December 28, 2010 2:59:09 AM > Subject: Re: [CentOS] Problems with motherboard support? INTEL DP43BF > > On 12/27/10 9:09 PM, robert mena wrote: > > Regular realtek fast ethernet. > > IMNSHO, realtek are pretty close to junk grade NICs. they have far too > many variations with far too many weird bugs when used for any more than > single user desktop kind of systems. > rl nics are toy nics. I wouldn't use them on production servers unless I have no choice For some reasons, see this, textually from FreeBSD's 5.4 if_rl.c: /* * 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. * sadly, things hadn't improved since then Fer