Archive for the 'Life' Category

AHCI PCIe SSDs

Sunday, October 7th, 2018

I thought we went from SATA connected (to AHCI board controllers) straight to PCIe connected NVMe protocol. Turns out there was a short time of PCIE connected SSDs with an AHCI controller. And of course Apple used them:

One can never have enough dongles^W proprietary connectors to lock users out, ..! :-/

Can we keep driving ICE cars? Fuel economy

Saturday, October 6th, 2018

My first car –I now drove for 6 years– is a 2012 Mini Countryman SD. Usually I accelerate softly, follow in slipstreams and engine brake. In other words some form of light hypermiling. So with our Countryman SD, which has the 2L turbo-charged Diesel engine and a classic torque converter automatic transmission, even without start/stop automatic I get:
Mini Countryman SD 2012 - 2L Diesel:
@100km/h: ~5 L/100km
@120km/h: ~6 L/100km

Now we may have to switch to something non Diesel soon. Electric is not yet an real option, as I usually do not drive in Berlin, and only driver longer distances, e.g. thru Germany or neighboring countries (in Berlin I walk & public transport). I also do not like the Tesla all-touch controls as well as their spare part and such policy. I may consider an BMW i3, however, for a start I test drove a base Porsche Macan, 2L gasoline to experience an quality upgrade after 6 years. This was intentionally the small engine, to target better fuel economy, 2L gasoline, also turbo-charged but with PDK, double clutch transmission and finally WITH start/stop automatic. I actually had to drive really carefully, a bit more hypermiling to even reach:

Porsche Macan 2017 - 2L Super+:
@100km/h: ~8 L/100km
@120km/h: ~10 L/100km

I have to say I was hoping for a little less. Now this was the base engine, not the 3L V6, not an 911, Ferrari, Lamborghini, or McLaren. AND driving really slowish. Now even when I driver our Mini Countryman I’m usually one on the slower side to do my part in slow down global warming and usually other driver overtake more on the crazy side. When you watch some famous car YouTubers you probably understand what I mean. And they drive sport cars, Audio R8, Lamborghinis, Ferraris, McLaren you name it. And they accelerate like crazy. So I estimate they consume more like 20 L/100km :-/

Now my question: In this day and age, of global warming, causing forrest fires, hurricanes, floods and more. Why are not more people thinking about this? Heck, even all the non-YouTubers, normal people overtaking me with 160, 200 km/h or even more when I roll 120-130 in other’s slipstream, consume way more than they realistically need to. They need to waste their momentum for other drivers, construction sites and regular speed limits anyway, and arrive how many few percent faster than us hypermiling with 120 in other’s slip stream? When I watch many of those drivers I estimate they could easily save 50% if not more of their consumption, ..!

Is is not clear that we need to do something?

This is also quite significant price-wise, to drive 1000km @ 120 km/h – German € gas (Super+) and Diesel prices of today:

MINI Countryman SD: 6L x 10 x 1.31€ = 78.60€
Porsche Macan: 10L x 10 x 1.54€ = 154.20€

And finally my Re:score:
Fuel economy: 3
Practicality: 6
Comfort: 5
Features: 7
Quality: 7
Styling: 7
Handling: 7
Acceleration: 4
Cool factor: 5
Value: 5
Total: 56 of 100

At first I wanted to rate it Doug DeMuro score compatible, but then it struck me that he does not even have a fuel economy rating. Priorities! Guess he only factors it into “Practicality”, if at all. I therefore scratch the quite useless “Fun factor” while he had “Cool factor” already anyways, ..!

Finally the first AMD ThinkPad!

Friday, September 21st, 2018

For decades fans of AMD, the inventor of x86-64, GPU infused APUs, and avoiders of a 100% Intel x86 monopoly where longing for a really high end quality machines, like IBM^W Lenovo ThinkPads. The dream came finally true, with AMD Ryzen w/ Vega gfx ThinkPads A285 and A485 this year.

This is a developing story, we will update with a review in a day or two.

Resist NVidia, especially for Linux

Friday, September 7th, 2018

So I do Linux kernel, driver, libraries, gcc, development since 1998. A little bit everywhere, all over the place. X86, ARM, PowerPC, SPARC you name it. I contributed to the Linux distribution ROCK Linux, later became stable release maintainer, and still run the fork #t2sde for embedded and special custom Linux distributions. My company ExactCODE was involved in many embedded projects and development like that, and in 2008 a customer wanted to base a product on the Nvidia Tega SoC, so I wrote Nvidia if they could release us any register level spec, even under NDA, to work on such a project. To my surprise I got an answer, but it was a simple one-liner, and not really what we needed to hear:

How is your Windows CE experience? We are not supporting Linux on Tegra.

Received: from hqnvupgp03.nvidia.com (Not Verified[172.17.102.18]) by hqemgate03.nvidia.com
id ; Tue, 22 Jul 2008 12:56:40 -0700
Subject: RE: NVidia SoC SPECs for Embedded Linux systems
Date: Tue, 22 Jul 2008 12:57:03 -0700

How is your Windows CE experience? We are not supporting Linux on Tegra.

—–Original Message—–

For the currently engaging projects we need solid 3D support in
our portfolio we would kindly ask for the possibility to sign an NDA
to receive register level specs support NVidia’s latest integrated
embedded SoC’s in our boards support offerings.

Just for those why I can not, and will never recommend chips without register level data sheets available to developer, ..!

AT command notes

Thursday, March 15th, 2018

so it is that time of the decade again, that you need to poke with some AT modem commands, e.g. for 3G / LTE networks, …

Does the SIM card need a PIN?
at+cpin?

Enter the PIN if required:
AT+CPIN=1234

Current network:
AT+COPS?

Update: special service numbers, e.g. balance:
AT+CUSD=1,”*100#”

List of early computing systems [WIP]

Monday, March 12th, 2018

I think we initially had a 286 without HD, nor color graphics
my father’s 386sx25 w/ 2MB RAM for what feels forever
gifted free NEC V20 XT clone thing
Pentium 120
IDT WinChip2 240
AMD K7 Athlon 600
AMD K7 Athlon 1GHz?
Sun Ultra 5 4/2002
Sgi Octane 11/2005
iBook G3 750?

GCC becomes slower and slower

Thursday, January 18th, 2018

As visible on my other posts, also on twitter and instagram I’m working on some vintage machines with our #t2sde the other weeks. Now only did the new GCC versions feel slower and slower, where even EPYC datacenter servers took like twice as long to bootstrap some $sysroot, … I did a quick mips64 build and install to the R10000 mips64 Sgi Octane. A hello-world.c compile is like 20% slower from 4.9.4 to 7.2.0 (N32 user-land):

# gcc –version
gcc (GCC) 4.9.4
# time gcc hello.c
user 0m1.080s

vs.

# gcc –version
gcc (GCC) 7.2.0
# gcc hello.c
user 0m1.290s

glibc minimum linux kernel version

Sunday, December 31st, 2017

Note to self:

glibc-2.13: at least 2.6.12… ok (mips64)
glibc-2.19: minimum kernel version reset to 2.6.16 (mips64)
glibc-2.21: at least 2.6.32 (mips64)

to be extended.

Also, turns out the FP NAN representation was recently changed for IEEE 754-2008 on MIPS around Linux kernel version 4.5.0, and glibc 2.23.

Update: On a similar note: GCC 4.4 now supports the MIPS R10K, R12K, R14K and R16K processors.

Update 2: i386 removed with Linux kernel 3.8, last glibc without NPTL for i386 LinuxThreads: 2.3.6?

Update 3: sparc32/sun4c removed with Linux kernel 3.5.

low-level format a spinning hard drive

Wednesday, December 27th, 2017

On this vintage Unix workstation machine I still got one of those spinning SCSI drives. The one in the SPARCstation 2 –spinning with 7200rpm, from 1999!– had some bad blocks at the end. First I partitioned it so that the OS would not touch them, but as I wanted to re-install a new, slightly different T2 build I wanted to try to get rid of this bad blocks. From the spec it sounds like those old drives may only re-map reserve spare blocks on low-level format, as opposed to any write like modern disk drives do. “Flawed sector reallocation at format time”, however, the document also mention “Programmable auto write and read reallocation”, “Reallocation of defects on command (Post format)” and even “Full automatic read and write reallocation” hm, … confusing.

Anyways, I did not really wanted to do a longer term install with this bad blocks so I tried the sgutils’s sg_format for the first time ever. Little bit of a scary thing, and you should certainly not do this light hearted. After issues the SCSI FORMAT command, the drive is busy and won’t respond to regular SCSI commands. I run for an hour, so I guess it was stuck ad some bad area. I turned if off, guessing this may render it bricked, and it came back online without responding to SCSI READ and WRITES, … I issues another FORMAT; in the hope it may complete, and after only some minutes it did, ..! Yay, good luck.

So do not try this too easy and too often. I still have to re-read the drive to see if it still gives read errors, or if the reallocation re-mapping of reserve sectors was successful.

CPU support lost in the Linux kernel

Saturday, December 23rd, 2017

For those enjoying tinkering with vintage, retro computer gear: Linux was the kernel and OS supposedly supporting every CPU, smart toaster and coffee machine under the sky.
Unfortunately with all the high massive parallel, performance state of the art tinkering some vintage maintenance burden was recently dropped over the years. Case in point: the original Intel 80386 which lacks the CMPXCHG instruction introduced with the i486, in the Linux kernel 3.8. And also the early Sun SPARC v7, Cypress, which even lacked hardware multiply and divide, somewhere around the kernel release 3.4, … :-/

Update: It also becomes increasingly difficult to configure kernels less than ~2.6MB required for booting on ancient sparc32 Sun machines, … :-(

Update 2: those apparently also required “special” SCSI CD-ROM drives supporting 512 bytes sized sector reads, as opposed to 2048 sized sectors as used by standard PC drives, ..?