I ran into a delightful irony trying to help a student get set up for the embedded systems lab I’m running this semester: Neither Keil MDK ARM (a first-class ARM development environment) nor the Stellaris ICDI Drivers (TI’s programming/debug interface … Continue reading
I’ve been idly looking for one of the mid-90s ThinkPads known to have perfect OpenStep/Rhapsody support for years as a fun collector piece, but been unwilling to pay eBay prices. The other week I scored a pristine IBM ThinkPad 560E for $20 in a Shopgoodwill auction, below is notes on getting it up and running, plus some relevant history and plans.
Continue readingThis post is a retro post on a retro topic – a repair I did in 2017 on a monitor made in 1991. I got a question about (probably) the same problem in another venue and realized I never put it online. I managed to dig up my pictures and notes, so there is useful information to be shared.
The end of my (2016) post about Recapping my Macintosh LC I discovered that my matching Apple 12″ Macintosh RGB Monitor ( M1296 ) was going pear-shaped, and speculated that I’d need to recap it.
Continue readingI have a machine with SSH exposed on one high-numbered nonstandard port forwarded through a NAT. A few days ago I noticed some log noise about failed SSH logins and turned on fail2ban with sane defaults. It banned almost 300 … Continue reading
I had my dear old Macintosh SE out for a health check as I slowly extract my vintage computer collection from the (unconditioned) place I’ve been keeping it at my parents house to the basement of the place I’m renting. It had a couple interesting findings that seem worth putting online, including another floppy drive rebuild and a slightly elaborate fan replacement.
Continue readingEven though I haven’t done any work in that area in years, I got pulled into the Supercomputing conference again this year. Can’t complain, it’s always fun. UK’s combined booth looked good this year
Far corner is a little updated TinyTitan style Raspberry Pi cluster with a interactive CFD demo running on it that the CCS folks have been playing with, that thing in the leading corner is a cute flip-dot “quantum computer” model we built as a front-end for a 16-bit instance of Hank’s parallel bit-pattern computing system that can do quantum algorithms efficiently on a conventional platform – set in the corner of the booth like
He did surprisingly well with this approach.
The exhibit floor was even more dominated by cooling tech this year. Exciting finds are the coming of very open (Open Compute Project, Coreboot + Open Network Linux) white-box 100GBE switches at reasonable prices, Fujitsu’s A64fx ARM with SVE and obscene memory bandwidth parts actually landing in systems, and (just because it tickled me) pre-wired fully populated Clos topology 100G cable harnesses. The other dominant species was AI woo; my body is ready for AI Winter 3.0.
Google photos album of my annotated show floor photos is here.
That MSEE that I was going to finish in 2011, 2013, and 2015? I blew a couple months in the last year to get all the ducks in a row and actually collected it before the credits expired. Huge thanks to Dr. Aaron Cramer, the current DGS for UK’s ECE department who went to great lengths to deal with the bureaucratic issues my lackadaisical attitude about credentials created.
Thesis is “A Compiler Target Model for Line Associative Registers” document and defense slides with notes linked.
The LARs design is fundamentally interesting, but the compilation work the MS is based on is not my favorite work I’ve done. The core initial assumption (that LAR allocation and register allocation were more-or-less the same problem) turned out to be very, very wrong, and the implications of that wrong assumption turned out to be far reaching, turning a 2-year MS into a decade-long ramble. It’s not as depressing as I thought it would be when I tried to finish in 2015 (and was blocked by bureaucratic fuckery) because I did eventually determine that LARs aren’t subject to the “you can’t statically schedule around dynamic memory behavior” thing that doomed VLIWs, and in fact LAR allocation can be done greedily in ways that register allocation cannot.
The thesis is more or less assembled from three false starts plus the final effort; my initial research start with the wrong assumptions, my “oh, we’re wrong, but it’s OK” pass, and my “oh shit, we’re screwed, this won’t work and there his historical evidence to show it” pass, plus the final “I’ve figured out how this is tractable and possibly even desirable, but I’m out of time and fucks, so here’s the rough solution” pass.
I formatted the thesis in LaTeX (of course), using the ukthesis.cls class I found on the UK Math site that Eric Stokes, a former student, made a decade and change ago since UK is too chickenshit to provide a valid one of their own. I did have to hack it a little bit, turn off some features, tweak the front matter, etc. to make it acceptable to the graduate school, and update a few things (eg. adjusted to use biber for references). There are a few things in the document that should be in the class, and things in the class that should be in the document, but the easy-to-fix stuff is fixed. Minimal example pulled from the accepted version with makefile and such here to save future students the extra annoyance.
The presentation is in beamer using the Owl theme, which was a delightful recent discovery – someone has made a beamer color scheme with a dark background and colors that actually look good on a projector. I (much to one of my committee member’s disappointment) went with the bullets-to-keep-me-on-track-while-I-talk style slides instead of my usual “amusing semi-relevant pictures to key off of” scheme.
It’s nice to be done and only have one, significantly less depressing, long-term academic project people are grumpy about my progress on.
I picked up a refurbished Dell Latitude E7250 (Dell’s “Premium” 12.5″ laptop, just over a generation out of date) because the little loaner Inspiron 11-3000 I’d been using as my carryin’ around laptop had become unacceptably shitty at essentially all the things I wanted to use it for. The E7250 is Superb, with notes:
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I’m back from SC’17, and to complete annual tradition, some thoughts:
Also, a pile of pictures from the show floor.
