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Comment Re:routine IT work (Score 4, Insightful) 307

Why do people keep saying that over and over again?

It's easy. You write a test suite that pretends to be a real user. You script it so there's some actions that aren't just "do A do B do C." You make them make errors. You have them put in garbage details. You have them fill out the forms incorrectly or incompletely. You have them skip pages or press "back".

Then you add a "pretend I'm the internet!" layer in between that simulates latency, so you make sure that your servers can handle the number of concurrent requests going on. A lot of not-so-seasoned web developers still fall for the "it worked on the LAN to 100,000 users, why not on the internet?" latency fallacy. Increased latency (due to RTT, packet drops, TCP retransmits, etc) leads to having more and more sessions going concurrently. That ties up resources at the server end.

Then you add a "pretend shit breaks!" layer. Ie, the user internet connection breaks. They forget and come back after a while, and hit the restart page. The connection dies half way during the transaction.

Then, once you've written that, you create 5 million instances of that. 100,000 per box sounds about right.

This isn't 1995. Computers are really god damned fast.

-adrian

Comment Re:pfSense (Score 1) 193

11n will work on Atheros hardware when they either/or:

* update pfsense to work against FreeBSD-10;
* start releasing snapshots of pfsense that work against FreeBSD-HEAD;
* backport the net80211, driver and userland tools from -HEAD to -8 (which I've done a few times, I've just not committed it to FreeBSD.)

11ac is a different story. I'm going to let the Linux side shake out before I start work on the FreeBSD 802.11ac support.

-adrian
(FreeBSD wireless maintainer.)

Comment Re:LaTeX (Score 2) 160

Why? Seriously? Because you want your print layout to be tightly controlled?

It's totally practical to do large scale document editing without WYSIWYG. Know why? Because we all did it before word 6.0 became a defacto standard. We would concentrate on document content first, then design a layout, then flow the content into that layout. Yes, like the HTML/CSS split.

These days people do poster layouts in _excel_.

Gah, sometimes I wish my beard were longer.

Comment Re:only *exact quoted text* is wrong (Score 3, Informative) 327

Erm.

The IBM PC, PC/XT has an 8088 (or clones with 8086's) that has a 20 bit address bus. It's still a megabyte, no matter what.

It doesn't matter where you put the BIOS - beginning or end. It's still a megabyte.

The BIOS is up the end there because the 8088 reset jump vectors are at the end of RAM, not the beginning (like the Z80, etc.) So you need to have something at that memory range for the CPU to start executing.

The 8086/8088 software interrupt vectors are at the beginning of your address space. So, there needs to be RAM there. The interrupt handler, NMI handler and all the software vectors can't be in ROM - well, they can be, but then they'd have to jump to RAM at some point to do anything flexible.

So, you:

* need RAM in the first 4k for jump tables and such (0x00000000 -> 0x00001000)
* need ROM at the end for the reset/power-on vectors .. so, the IBM PC memory map makes sense.

The IBM PC architecture also assumed people would build ROM add-on applications, like BASIC (which they did) but also word processors, spell checkers, etc. That's why there's 8 ROM slots on the PC and PC/XT. But people soon adopted disk applications rather than ROM applications.

So, I don't buy that "it's Gates' fault." The only things I can see he could've done differently are:

* advocate a 68000 CPU - but then he'd have issues at 16MB - and Amiga/MacOS had exactly that
* add more RAM and less peripheral address space - but you're still capped at 1MB
* advocate for an EMS (page-flipping) architecture early on, and encourage people to make use of it.

Comment Re:Political Correctness has no place in Kernel De (Score 1) 1501

My point wrt the Civil Rights Movement was not anything to do with skin colour. It was that a growing group of people decided not to simply subscribe to the rules and customs of the community around them and started increasingly taking a stand against it.

I'm surprised people didn't connect the dots.

Whether or not I agree with Sarah isn't the point. It's that she's able to stand up for what she believes in, going against the community as a whole, and (at least a little bit) forcing a few people to temporarily re-evaluate the idea of what the group norms are. I'm glad she's trying.

Comment Re:wasteful on spectrum (Score 3, Informative) 107

The 802.11ac spec lets you do that.

You can use 40, 80, 80+80 or 160. Right now I think everything is shipping 80 only, but I could be wrong. But the chip is allowed to transmit on whichever channel is free. If the primary 20MHz channel is free, it transmits on that. If the Primary and Extension 20Mhz channel are both free (ie, the "HT40" channel in 802.11n parlance) it transmits on that. If all 80MHz is free, it transmits on that.

It's pretty nifty stuff.

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