em bad performance

[Danny Braniss]

> On Thu, Dec 22, 2005 at 12:24:42PM +0200, Danny Braniss wrote:
> D> ------------------------------------------------------------
> D> Server listening on TCP port 5001
> D> TCP window size: 64.0 KByte (default)
> D> ------------------------------------------------------------
> D> [  4] local 132.65.16.100 port 5001 connected with [6.0/SE7501WV2] port 58122 
> D> (intel westvill)
> D> [ ID] Interval       Transfer     Bandwidth
> D> [  4]  0.0-10.0 sec  1.01 GBytes   867 Mbits/sec
> D> [  4] local 132.65.16.100 port 5001 connected with [5.4/SE7501WV2] port 55269 
> D> (intel westvill)
> D> [ ID] Interval       Transfer     Bandwidth
> D> [  4]  0.0-10.0 sec   967 MBytes   811 Mbits/sec
> D> [  5] local 132.65.16.100 port 5001 connected with [6.0/SR1435VP2 port 58363  
> D> (intel dual xeon/emt64)
> D> [ ID] Interval       Transfer     Bandwidth
> D> [  5]  0.0-10.0 sec   578 MBytes   485 Mbits/sec
> D> 
> D> i've run this several times, and the results are very similar.
> D> i also tried i386, and the same bad results.
> D> all hosts are connected at 1gb to the same switch.
> 
> So we see a strong drawback between SE7501WV2 and SR1435VP2. Let's compare the NIC
> hardware. Can you plese show pciconf -lv | grep -A3 ^em on both motherboards?

on a SE7501WV2:
em0 at pci3:7:0:   class=0x020000 card=0x341a8086 chip=0x10108086 rev=0x01 
hdr=0x00
    vendor   = 'Intel Corporation'
    device   = '82546EB Dual Port Gigabit Ethernet Controller (Copper)'
    class    = network

on a SR1435VP2:
em0 at pci4:3:0:   class=0x020000 card=0x34668086 chip=0x10768086 rev=0x05 
hdr=0x00
    vendor   = 'Intel Corporation'
    device   = '82547EI Gigabit Ethernet Controller'
    class    = network

thanks,
	danny