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Comment "20Gb/s" will bring useful 10GbE (Score 4, Interesting) 301

I do 10GbE drivers, and the previous generation of tbolt did not really offer 10Gb/s of usable bandwidth to PCIe devices, it was more like 8Gb/s:

If you recall, tbolt muxes PCIe and Display Port. On the PCIe side, the thunderbolt bridge passed 2 lanes of Gen2 PCIe through to devices. Since Gen2 is "5GT/s" per lane, you'd think you'd have 10Gb/s. But not really, as "10Gb/s" does not take into account PCIe overhead, which can be about 20% of the data transfer rate. So on the original "10Gb/s" thunderbolt, you were lucky to get 7Gb/s transfer rate from 10GbE NIC, once you also add in network protocol overheads.

Having a bus-constrained NIC leads to all sorts of weird problems when receiving data.. With flow control disabled in combination with bursty transfers, you often see far less than the 7Gb/s peak, as TCP hunts around to find the constraint and recover from frequent packet loss events.

It sounds like they've built the new part from 2 lanes of Gen3 PCIe, which should be good for ~16Gb/s of usable bandwidth. This is a very welcome change, as 16Gb/s should be enough for a single-port 10GbE NIC running at full speed, and a disk controller talking to a fast SSD or an external RAID array that can deliver ~750MB/s (bytes) of I.O.

Just don't try to use a bonded 2 port 10GbE NIC, or you're back at the bandwidth constrained problem.

Comment I had a Mac desktop & reverted to Linux (Score 1) 965

In ~2007, after the birth of my first child I had very little time. So I thought to myself "I don't have time to keep up with maintaining a Linux desktop" and I bought a nice iMac, and moved from Linux to Mac.

The experience I had was that everything that was a royal PITA on nix at the time (web browsing, audio, skype, video, photo management, suspend/resume, printing) "just worked" on the Mac. Hurray!

But the problem I had was that the unixy stuff stuff I needed to do my job (X11 across multiple monitors, emacs, serial console control, local command-line tools, etc) did not just work, and was more a PITA to maintain on MacOSX than the flashy stuff was to maintain on Linux. The final straw was when I upgraded to Leopard, and multiple monitor support in X11 was totally hosed at the time of the initial release.

In the end, I wound up giving the iMac to my in-laws after about 9 months, and building another whitebox for 1/2 the price of the iMac, and I have been happy ever after. That 2007 whitebox is now running Kbuntu, and is my 6 year old's PC (while I've built myself a newer one..)

Comment Re:NDA (Score 2) 85

It is probably not a bad thing.

Back in the day, I did FreeBSD drivers / platform support for DEC Alphas. I would occasionally get hardware and/or docs under NDA from DEC. The NDA basically said I could write open source drivers, but I could not share the documentation. This is how a lot of Linux / BSD hardware support still works.

Comment Re:WHAT? (Score 1) 155

Sorry, I have an x86/amd64 + DEC alpha historical bias, and don't really know a lot about ARM.

As a user, having the "southbridge" stuff integrated onto the CPU card means that you're essentially getting a whole new motherboard when you replace this CPU card. I always view a whole new motherboard as a whole new set of problems, in terms of potentially buggy hardware and drivers. At the very least, it is seems problematic in terms of having to upgrade your kernel to support the latest stuff. In the x86 world, as long as the vendor hasn't changed the CPU socket, you can generally drop in a new CPU with just a BIOS upgrade, and you don't need to worry that you might get a whole new set of buggy peripherial chips.. I've often done that with AMD CPUs.

Comment Re:WHAT? (Score 1) 155

Maybe a dumb question, but why do you put the core peripherals (USB, Sata, ethernet, VGA) on the CPU card, each requiring these pcmcia pins. Why not use a PCIe interface, and leave the peripherals to the tablet / laptop / motherboard / tv / etc vendor? It seems like this would allow for greater differentiation between "system" vendors, and would require less integration efforts from CPU vendors.

Comment Plymouth & grub2, no thanks (Score 2, Insightful) 96

Maybe I'm just old and grumpy, but all of this fancy new crap that obfuscates the boot process really ticks me off. If a machine has trouble booting, the last thing I want is some fancy gui with a pretty stop-watch ticking endlessly at me, rather than seeing "NFS server foo not responding" in black and white. So now rather than having just the actual problem to fix, I've got to use a second machine to figure out how to shut off the god damned gui (or how to get into the grub menu) before I can even get a hint what the actual problem might be.

Now get off my lawn.

Comment Re:2007 Mac Mini couldn't be upgraded (Score 1) 397

If you really want to upgrade, you should be able to "hackintosh" your mac. I did this to test 64bit drivers on a macpro1,1. It worked well enough for what I needed it (running 64b kernel), however, I would not use this setup for a daily use machine, as the video card acceleration went away, the power usage increased, etc. I'd keep a separate partition for daily use, and only boot into the "hackintosh" 10.8 setup when you need to work on your project.

Comment Re:Fastest to the finish line (Score 1) 209

If this package is indeed capped, it is just as stupid and sad as the 5GB caps on 4G wireless data plans.

If my sleepy math is right, you reach the old 250GB cap in a little less than 2 hours and the rumored new 300GB cap in a little over 2 hours. If they stick with the proposed 10$ per 50GB overage charge, you can enjoy paying about $25/hr to use your 305Mb/s connection after the first 2 hours.

Comment Re:Hackintosh your Macintosh. (Score 2) 417


I've been doing the same thing for years with a similar Macpro1,1 that I use as a dev box for 10GbE ethernet drivers. When 10.6 previews offered a 64b kernel, I was majorly pissed that I had a less than 2 year old $3000 machine that I could not use to test my drivers in 64-bit mode. So I did what you did & turned my MacPro into a hackintosh.

Comment Re:It's Still Available, should I buy it? (Score 1) 696

Yes. It is awesome. I got mine 2 months ago, and could not be happier. My wife has my old Nexus One.

The one thing you need to be a aware of is that this phone is HUGE!. Make sure to get a case that has some kind of belt-clip built in, as the phone + case will not fit comfortably in any stand-alone phone holster or most pants/shirt pockets. I'm probably going to have to just throw away the case I bought for it, or try to jury-rig some kind of belt clip into it.

Comment Somebody suggest an environment for me (Score 2) 663

I've run X11 since 1989. I started with TWM, then CTWM, then KDE.

KDE2. was great, KDE3 was fine, KDE4 is bloated. I don't care about eye candy. I don't care about UI guidelines thought up by some hipsters. I don't want widgets. I don't want spinning 3d cubes when I change workspaces. All I want is a desktop env. that works. What I care about:

- The ability to customize window the window manager enough to map Alt-mouse-1 to move, Alt-mouse-2 to resize and Alt-mouse-3 to iconify. These are hardwired in my brain after 23 years.

- The ability for the icon manager to work vertically, so I can stick it on the side of my workspace, rather than the top or bottom. Today's stupid widescreen monitors are too cramped vertically, and I begrudge any pixels taken away from my applications

- multiple desktops

- multiple monitor support

- no fancy GL stuff that screws up VLC or mplayer playing hardware accelerated video.

That's it. That's all. I could give a flying you now what about file managers, widgets, etc.

Comment our US daycare had 4yr old playing with real tools (Score 1) 754

When my then 4yr old son "moved up" to a new classroom in the co-op daycare we used at the time, I was pleasantly surprised to see they had a real workbench at child height with hammers, nails, a saw, screwdrivers, etc as one of their play "centers". My son enjoyed this, and was never injured.

I'm still surprised they were able to do that & not get sued by some moron. This was 2 years ago, though so they may have changed things..

Comment Re:AMD Linux support sucks (Score 4, Informative) 132

+1 I had an ATI in my last Linux desktop. Never again.

The proprietary fglrx drivers tend to have weird bugs and as you say, they drop chips that are old enough to have decent support. On the flip-side, the open-source radeon drivers tend to require various bleeding edge bits and pieces to work correctly, so they are nearly impossible to run on stable distros, like an Ubuntu LTS or a RHEL.

Nividia's proprietary drivers just work, once you finally figure out how to blacklist nouveau hard enough that it doesn't get loaded via the initrd. Plus they support VDPAU for projects like MythTV and XBMC.

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