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termie

Re:Making a micro Linux distro (2023) on Saturday October 25, 2025 @12:16PM (#45704986)
I've been working on a micro Linux distro for a couple of months now. User mode is just a single static binary (and a few files to support confidential microVM containers). The initramfs is such an interesting feature, the kernel knows how to unpack cpio archives and just magically drops you into a tmpfs and executes /init. You can have multiple concatenated cpio archives, and each can be compressed, and they all just overlay in sequence. There's an elegance to the design. I also had to write some code to unpack them and learned more than I wanted to.
Compare the size of the new air-cooled 40XX cards and the iChill 4090, which is tiny by comparison. The simple answer is just to use liquid cooling if you have a card using 400w. Then all the absurdity just goes away.
Rust is also discussed at 35:00 into the presentation, noting the lack of a spec, higher memory util, and no commmercial vendor.
Re:Why does musl make my Rust code so slow? on Tuesday May 05, 2020 @10:43AM (#23080528)
run a perf trace on both and see what jumps out
Re:Stupid Unix Tricks on Thursday October 17, 2019 @11:17AM (#21282943)
ProxyJump was added in OpenSSH 7.3 so systems from a few years ago might not support it. It does the same thing as ProxyCommand with -W %h:%p but you can’t set custom options for the jump connection with ProxyJump.
Re:Efficient string copying and concatenation in C on Thursday September 12, 2019 @05:24PM (#20956628)
Yes, the kernel will map virtual to physical however it sees fit, no guarantees there (at least not in user-space via glibc). Realloc will always return a virtually contiguous slice or NULL if it can’t. And you’re right, obviously all those potential subordinate mallocs would be inefficient. :) In this contrived FizzBuzz example case, you could pretty easily do the math and just malloc it all in one go at the start of the function. Fizz and Buzz are the same size, you would just need to add up the iota lengths and the trailing \0. If you take an arg for N (1..N) then stack allocations are not going to work. You need to statically declare their size.
Re:Efficient string copying and concatenation in C on Thursday September 12, 2019 @04:10PM (#20955906)
You can use realloc. It will try to use the existing contiguous span of memory, but if it cannot, it will malloc a new span and copy the previous bytes in and return a pointer to it.
Re:Electric version of Renault's low-cost Kwid on Tuesday September 10, 2019 @07:00PM (#20934782)
Someone has to make a business case to get the chargers on the street. There are questions like who owns the sidewalk, how to route sufficient power there, capital outlay for digging up the street and getting the charger there. All those costs and up and the revenue for a given charger is capped. People might pay a premium over the the cost of electricity, but how much? And they have to compete with free charging in many cases.
Re:Want 1.5TB of RAM in Your PC? It Will Cost You on Sunday September 08, 2019 @10:34AM (#20910798)
The throughput is amazing. The screenshot shows 28,375 MB/s — the capital B typically indicates Bytes whereas a lowercase b indicates bits, so your Gb/s translation is a little confusing. The latency is still much higher than main memory or Optane, but that might be fine for many applications.
The upcoming MKTME support in future Intel processors will hopefully make this problem simpler to solve.
Re:V100 Server On-Prem vs. AWS P3 Instance Cost Comparison on Tuesday February 19, 2019 @09:41AM (#19199188)
It is possible to sell (or buy) reserved instances in a secondary market: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ri-marke...
Re:Pwn2Own Vancouver 2019: Tesla, VMWare, Microsoft, and more on Tuesday January 15, 2019 @11:04AM (#18912104)
This is from mid 2017. "First notified Tesla on 31/08/2017 .. Tesla vehicles produced from June onwards use a new key fob". Not sure if the new fob is significantly better as the presentation is not clear there.
Re:What Is Going to Happen in 2019 on Wednesday January 02, 2019 @10:46AM (#18806894)
..by the Republican majority House of Representatives. It can be roughly equated to being charged with a crime. The Senate held a trial and voted for acquittal and therefore no action was taken. Two thirds of the Senate must vote to remove a President from office.
Re:Linux: IO without entering the kernel on Sunday December 16, 2018 @09:26AM (#18693151)
This is promising, but for dedicated high-performance I/O I am much more interested in how the SPDK is progressing. Avoiding syscalls is great, but without any benchmarks I wonder about the benefits over mmap and vectorizing. You still have to contend with locking, interrupts, copying, and ring 0 abstraction impedence.

[1] https://spdk.io

Re:Mac mini Late 2018 Teardown on Friday November 09, 2018 @09:00AM (#18414341)
Curious as to which 10Gb Ethernet controller is being used, no mention in the teardown. Anyone know?
Re:The annoying habits of highly effective people on Tuesday October 02, 2018 @07:31AM (#18120538)
That would seem to depend on the leadership. You might get the leader’s former job.
Perhaps the solid cells could be warmed up via some cheap coils powered by some bootstrapping liquid cells?
Re:Ternary Trouble in Perl on Sunday August 26, 2018 @08:05PM (#17848622)
Try more parenthesis or perlmonks.com
Re:AT&T updates firmware to block access to 1.1.1.1 on Wednesday May 02, 2018 @07:51PM (#16982171)
Curious to know if they block Google’s DNS servers as well. That 1.x space was a RIPE research segment, so it’s possible that some internal AT&T group was using it with the assumption it would not be publicly routable and got bit. I was enjoying the shorthand ping of 1.1 for my router at home until Cloudflare took it over. Needless to say, if that was the case for AT&T, their ‘fix’ is not at all acceptable.
Re:Tesla Semi on Friday November 17, 2017 @08:51AM (#15721914)
Still kinda giddy about the Roadster, too. Guilty — can’t get enough of Elon’s disruption (personal life aside) —- sue me or grab the pitchforks.. i’ll serve you lemonade. :)
Re:Tesla Semi on Friday November 17, 2017 @01:01AM (#15719367)
If the math works there — could now or over time — then once L5 hits imagine the possibilities. L5 trucks towing broken L5 trucks with a third taking the cargo. I missed the video, but I’d bet huge that needed tech is probably prototyped already, at least in the elonoggin. Well done Elon!
Re:Parallel processing with Unix tools on Saturday September 23, 2017 @09:14AM (#15319580)
Bash’s built-in wait is also handy when you want quick and simple parallelism. http://tldp.org/LDP/abs/html/x9644.html
Re:AWS announces per-second billing for EC2 instances on Monday September 18, 2017 @06:21PM (#15280198)
The reserved instance pricing model is really poorly implemented. You have to commit to an instance class and a region, and if you need to change you can, but there is some secondary market. When compared to a sustained use model, it is a disaster. Managing all that in a large org is a real pain in the ass.
Re:The Boring Company [video] on Friday April 28, 2017 @11:39PM (#14224913)
I wonder if you could make a big drill out of hundreds of hot swappable high torque Tesla motors that were intelligently geared and well mounted. Hot swapping battery packs from the underside of a car via automation was demonstrated years back by Tesla so learnings there could be used. Tesla uses a bunch of widely available 18650s for their packs and benefit from that same modularity, and I imagine big cost savings there for a drill that size even with a great deal of breakage in the array of motors.
"The Step Functions free tier includes 4,000 free state transitions per month." .. "$0.025 per 1,000 state transitions thereafter"

So Amazon has created a new calling convention, where conditional logic now also requires a context switch and JSON serialization. Then they charge you for the call .. $tdcall?

This will certainly have some useful applications, maybe someone will build an inexpensive data processing pipeline on top of it. Having seen many visual workflow tools through the years, most are simplifying complex underlying process, but these step functions and state transitions are modeling basic internal control flow with complex abstractions and little benefit other than retries with backoff.

The pure functional immutable nature of the data flow is ideally nice but tainted by the JSON. The parallelism is interesting, but it seems bolted on instead of a more powerful central part of the design.

Re:Using htop to generate a live website background on Saturday October 03, 2015 @11:52AM (#10324286)
If htop is unavailable, then you can hit the number 1 key in regular top on Linux to see individual CPU utilization.
Re:Introducing OpenBSD's new httpd [pdf] on Sunday March 15, 2015 @02:14PM (#9207401)
You are correct. I assumed MS Office put it there, not even considering that Comic Sans would be on OSX by default. Hah! It's an even more sublime statement now, as only the untainted free distributions out there don't see it.. and it's also directed at web hipsters, but the result there appears to be unintentionally ironic.
Re:Introducing OpenBSD's new httpd [pdf] on Saturday March 14, 2015 @04:04PM (#9203974)
You're right, they use it as a weapon of snark and for fund raising:

http://www.openbsd.org/papers/bsdcan14-libressl/mgp00025.htm...

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