Sunday, July 20, 2008

The GigE Saga Continues

I connected a second system to my GigE switch, and as usual, it was a bigger job than it should have been. Again, it was my fault: Any good system administrator will tell you that you should only make one change at a time. I made two. I swapped cases and enabled the interface.

The second system is a home-grown rack mount virtualization server with a Foxconn motherboard running an AMD X2-64 at about 2.1 Ghz. The 100meg NIC (e100) is on the .69 network and the 1Gig NIC (r8169) is on the .169 network. The meat of the matter, however are the transfer benchmarks.

The first test I did was with SCP.
$ date; scp test.iso doug@; date
Sun Jul 20 22:58:31 EDT 2008
test.iso 100% 489MB 2.8MB/s 02:56
Sun Jul 20 23:01:31 EDT 2008
Almost three minutes.
$ date; scp test.iso doug@; date
Sun Jul 20 23:02:27 EDT 2008
test.iso 100% 489MB 2.9MB/s 02:47
Sun Jul 20 23:05:18 EDT 2008
The time and through put are virtually identical, but then I honestly did not expect to see any difference in performance. At issue is the fact that SCP is speed limited.

Next NFS-- which I'm hoping will scream.
$ date; cp test.iso /net/; date
Sun Jul 20 23:21:05 EDT 2008
Sun Jul 20 23:23:06 EDT 2008
About two minutes. A little better than SCP.
$ date; cp test.iso /net/; date
Sun Jul 20 23:29:38 EDT 2008
Sun Jul 20 23:30:58 EDT 2008


That's a let down: 2:01 -vs- 1:20 I shouldn't be complaining about a 67% increase in transfer, but the line is ten times faster. I'm not even getting double the transfer rate. What's up with that?

Thursday, July 17, 2008

Palm Centro: HotSync

I spent nearly an hour trying to resolve this silly glitch...

While trying to HotSync, I kept getting the message:
Unable to initiate HotSync operation because the port is in use by another application.
No matter what I did, it wouldn't connect to my laptop. Turns out, Bluetooth was disabled on the Centro. I enabled Bluetooth, and the HotSync worked.

What made this so painful was the fact that on the Tungstun, if you tried an operation that required Bluetooth, it would tell you that Bluetooth was off, and ask to turn it on. Minor change, big headache.

Saturday, July 05, 2008

Linux GigE Card

Finally got a few minutes to start switching over to GigE. I've been disappointed with the lack of information on supported GigE cards available on the net. On a roadtrip to Phoenix, I stopped in at a Fry's and found a US Robotics card for $16 that claimed to support Linux.

I snagged the card and a D-Link DGS-2208 GigE Switch (on sale: $39.99!!!) and headed back to DC. Installed the card in an FC-4 machine, and after a fair amount of playing around, got it running. (The problem was my anal and uncalled for desire to have the card be eth2, rather than eth1.) I left the 100 Meg card in as eth0.

The card is a US Robotics 7902A and it loaded the r8169 driver. At the moment, all seems right:
[root@scully ~]# ethtool eth2
Settings for eth2:
    Supported ports: [ TP ]
    Supported link modes: 10baseT/Half 10baseT/Full
            100baseT/Half 100baseT/Full
    Supports auto-negotiation: Yes
    Advertised link modes: 10baseT/Half 10baseT/Full
            100baseT/Half 100baseT/Full
    Advertised auto-negotiation: Yes
    Speed: 1000Mb/s
    Duplex: Full
    Port: Twisted Pair
    PHYAD: 0
    Transceiver: internal
    Auto-negotiation: on
    Supports Wake-on: pumbg
    Wake-on: g
    Current message level: 0x00000033 (51)
    Link detected: yes
The big test come when I get the second system on the switch in the morning.