Logotron Genesis.

Oct. 7 Update: Removed experimental attempt to use “shlex” for support of double-quoted search (it broke parsing of single quotes in search strings.)
Oct. 4 Update: Introduced adjustable detector of bot disconnection. Removed broken Tape knob in reader.
Oct. 3 Update: Bvt’s bot [...]

“M” Performance… Pessimizations! or: SSE is a Scam.

This article is a continuation of the M series.

The vpatch given below entirely re-implements the TLB (MMU) of M to use SIMD instructions from the AMD64 SSE2 set.

Whereas previously TLB entries were kept in memory and searched iteratively, now we keep the Tags (3 byte each) sliced into three XMM registers, and search them in [...]

“M” Performance Optimizations.

This article is a continuation of the M series.

The vpatch given below speeds up the execution of M by approximately 30% (as measured by the Dhrystone benchmark.) It implements separate single-entry TLB caches for reads and writes; a set of fastpath exception handlers; and several other minor optimizations.

You will need:

A Keccak-based [...]

“M” Genesis.

M is a MIPS-III system emulator, written purely in AMD64 assembly to make optimal use of commonplace iron. As discussed previously.

M will run lightly-modified Linux kernels with strict logical isolation vs. the host (and vs. any other instances of itself.) That is, it in fact does exactly what e.g. QEMU fraudulently pretends to do.

To keep [...]

“Sometimes, at night, I dream about the boat.”

Below is an entirely unofficial translation of “Иногда ночью мне снится лодка”, by Alexander Pokrovskiy — an old sailor-turned-memoirist, AFAIK entirely unknown in the English reich.

On some nights, I dream about the boat. It is underway, beneath the water.
I dream about it after I’ve had a very tiring day.
The dream is [...]

Posted in: Books, Distractions, NonLoper, Philology by Stanislav No Comments

25 Years of Loud, Expensive Space Heaters.

A half-written draft of this piece has been living on my HDD for nearly half a year. Recent discussions re: the subject of “aging and death of PC irons” prompted me to dust it off and quickly post. Regularly-scheduled programming will resume shortly…

“The [...]

X-Ray Large-Format Kindergarten.

Below is the output of a new test-fire of the PCB radiography system, this time using FujiFilm “Super HR-T Medium Speed” (25×20 cm) film in place of the earlier self-developing dental Eco-30.

However, the time has not yet come to molest the MacIvory — first, we must characterize the film and the [...]

X-Ray Microscopy of Symbolics “Ivory” CPUs.

I currently have three Symbolics MacIvory CPUs. (Do you, reader, have one to sell? Please leave a comment!)

One is currently installed in a working machine and was not yet molested; the two remaining chips, I obtained in 2017 by bartering away a Symbolics 3620.

At some point I will cut one or more of the “Ivories” [...]

X-Ray Spectrography Kindergarten.

This article is a continuation of “X-Ray Microscopy Kindergarten.”.

Preliminary experiment with multi-energy x-ray (colour channel combination), distinguishing materials by absorption at different wavelengths.

The tube appears to exhibit some “heel effect” at the longer wavelengths.

Exposure: 75 sec. @ 35kV, 21kV, 20kV (R, G, B) [...]

X-Ray Stereography Kindergarten.

This article is a continuation of “X-Ray Microscopy Kindergarten.”.

Here, we see a stereo pair (approx. +/- 25 deg. one-axis rotation of the object from the horizontal plane, while film is stationary) of the device from before.

The vias are clearly distinguishable.

[...]

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