Monthly Archive:: October 2018

This paper presents an evaluation of the use of a high-level language (HLL) with garbage collection to implement a monolithic POSIX-style kernel. The goal is to explore if it is reasonable to use an HLL instead of C for such kernels, by examining performance costs, implementation challenges, and programmability and safety benefits.

The paper contributes Biscuit, a kernel written in Go that implements enough of POSIX (virtual memory, mmap, TCP/IP sockets, a logging file system, poll, etc.) to execute significant applications. Biscuit makes liberal use of Go's HLL features (closures, channels, maps, interfaces, garbage collected heap allocation), which sub- jectively made programming easier. The most challenging puzzle was handling the possibility of running out of kernel heap memory; Biscuit benefited from the analyzability of Go source to address this challenge.

On a set of kernel-intensive benchmarks (including NGINX and Redis) the fraction of kernel CPU time Biscuit spends on HLL features (primarily garbage collection and thread stack expansion checks) ranges up to 13%. The longest single GC-related pause suffered by NGINX was 115 microseconds; the longest observed sum of GC delays to a complete NGINX client request was 600 microsec- onds. In experiments comparing nearly identical system call, page fault, and context switch code paths written in Go and C, the Go version was 5% to 15% slower.

Among many of Intel's announcements today, a key one for a lot of users will be the launch of Intel's 9th Generation Core desktop processors, offering up to 8-cores on Intel's mainstream consumer platform. These processors are drop-in compatible with current Coffee Lake and Z370 platforms, but are accompanied by a new Z390 chipset and associated motherboards as well. The highlights from this launch is the 8-core Core i9 parts, which include a 5.0 GHz turbo Core i9-9900K, rated at a 95W TDP.

Microsoft's rollout of the Windows 10 October 2018 Update has arguably been one of its most troublesome releases in recent times. While previous updates have also had issues, this one boasted particularly serious ones such as user files being deleted, bugs in the Task Manager, Intel driver incompatibility, internet connectivity issues, and more.

Following widespread reporting of these issues, Microsoft has now pulled the Windows 10 October 2018 Update from circulation.

The Apple A12 is a beast of a SoC. While the A11 already bested the competition in terms of performance and power efficiency, the A12 doubles down on it in this regard, thanks to Apple's world-class design teams which were able to squeeze out even more out of their CPU microarchitectures. The Vortex CPU's memory subsystem saw an enormous boost, which grants the A12 a significant performance boost in a lot of workloads. Apple's marketing department was really underselling the improvements here by just quoting 15% - a lot of workloads will be seeing performance improvements I estimate to be around 40%, with even greater improvements in some corner-cases. Apple's CPU have gotten so performant now, that we're just margins off the best desktop CPUs; it will be interesting to see how the coming years evolve, and what this means for Apple's non-mobile products.

On the GPU side, Apple's measured performance gains are also within the promised figures, and even above that when it comes to sustained performance. The new GPU looks like an iteration on last year's design, but an added fourth core as well as the important introduction of GPU memory compression are able to increase the performance to new levels. The negative thing here is I do think Apple's throttling mechanism needs to be revised - and by that I mean not that it shouldn't throttle less, but that it might be better if it throttled more or even outright capped the upper end of the performance curve, as it's extremely power hungry and does heat up the phone a lot in the initial minutes of a gaming session.

Microsoft is currently running an interesting set of hardware experiments. The company is taking a souped-up shipping container stuffed full of computer servers and submerging it in the ocean. The most recent round is taking place near Scotland's Orkney Islands, and involves a total of 864 standard Microsoft data-center servers. Many people have impugned the rationality of the company that put Seattle on the high-tech map, but seriously - why is Microsoft doing this?

There are several reasons, but one of the most important is that it is far cheaper to keep computer servers cool when they're on the seafloor. This cooling is not a trivial expense. Precise estimates vary, but currently about 5 percent of all energy consumption in the U.S. goes just to running computers - a huge cost to the economy as whole. Moreover, all that energy used by those computers ultimately gets converted into heat. This results in a second cost: that of keeping the computers from melting.

The Commodore Datasette recording format is heavily optimized for data safety and can compensate for many typical issues of cassette tape, like incorrect speed, inconsistent speed (wow/flutter), and small as well as longer dropouts. This makes the format more complex and way less efficient than, for example, "Turbo Tape" or all other custom formats used by commercial games. Let's explore the format by writing a minimal tape loader for the C64, optimized for size, which can decode correct tapes, but does not support error correction.

The Android app mirroring will be part of Microsoft's new Your Phone app for Windows 10. This app debuts this week as part of the Windows 10 October 2018 Update, but the app mirroring part won't likely appear until next year. Microsoft briefly demonstrated how it will work, though; you'll be able to simply mirror your phone screen straight onto Windows 10 through the Your Phone app, which will have a list of your Android apps. You can tap to access them and have them appear in the remote session of your phone.

We've seen a variety of ways of bringing Android apps to Windows in recent years, including Bluestacks and even Dell's Mobile Connect software. This app mirroring is certainly easier to do with Android, as it's less restricted than iOS. Still, Microsoft's welcoming embrace of Android in Windows 10 with this app mirroring is just the latest in a number of steps the company has taken recently to really help align Android as the mobile equivalent of Windows.

The Windows 10 October 2018 Update is version 1809, and while it's the latest feature update, a major focus of this update was fixes and refinements. Some features, like Sets and Alt-Tab bringing up browser tabs, have been delayed, and despite Sets not having returned yet in Skip Ahead builds, Microsoft has assured Neowin that the feature is still going to return.

Four lobbying groups representing some of the largest telecom companies in the country filed a lawsuit Wednesday opposing California's net neutrality law in an attempt to stop it from going into effect next year.

The four industry groups filing the lawsuit were USTelecom, CTIA, NCTA, and the ACA - groups which represent telecom corporations like AT&T; Verizon Wireless; Charter Communications; and Comcast, and mobile companies like T-Mobile. This is the second lawsuit filed following the passage of California's net neutrality law on Sunday. The first was fired off by the Department of Justice only hours after the bill received its final signature from Governor Jerry Brown.

This maintenance version features user experience enhancements and reliability improvements, and a more capable Archive Manager program. Bug fixes cover a number of GUI flaws and memory leaks, and some of the low-level network infrastructure code has been refined.

Visopsys is an alternative operating system for PC compatible computers. In development since 1997, this system is small, fast, and open source. It features a simple but functional graphical interface, pre-emptive multitasking, and virtual memory. Though it attempts to be compatible in a number of ways, Visopsys is not a clone of any other operating system.

The Spectrum was not the first Sinclair computer to make it big. It was, however, the first to go massive. In the months prior to launching, 'The Computer Programme' had aired on the BBC, legitimising the home micro computer as the must have educational item of the 1980's. For Sinclair and the ZX Spectrum the time was right, parents were keen, and the kids were excited. Games would soon be were everywhere thanks to all the kids programming their brand new Spectrums.

A major success factor, the one that gave the Spectrum its name, is the computer's capacity to generate a spectrum of colours. The micro is capable of generating 16 colours; 8 low intensity colours and 8 matching bright variants. It's hard to imagine now, but in 1982 these 16 colours were enough to start a home computer revolution. Richard Altwasser, the engineer employed by Sinclair to develop the Spectrum's graphic systems, was setting a new benchmark with some very innovative ideas.

Web users are increasingly turning to ad blockers to avoid ads, which are often perceived as annoying or an invasion of privacy. While there has been significant research into the factors driving ad blocker adoption and the detrimental effect to ad publishers on the Web, the resulting effects of ad blocker usage on Web users’ browsing experience is not well understood. To approach this problem, we conduct a retrospective natural field experiment using Firefox browser usage data, with the goal of estimating the effect of adblocking on user engagement with the Web. We focus on new users who installed an ad blocker after a baseline observation period, to avoid comparing different populations. Their subsequent browser activity is compared against that of a control group, whose members do not use ad blockers, over a corresponding observation period, controlling for prior baseline usage. In order to estimate causal effects, we employ propensity score matching on a number of other features recorded during the baseline period. In the group that installed an ad blocker, we find significant increases in both active time spent in the browser (+28% over control) and the number of pages viewed (+15% over control), while seeing no change in the number of searches. Additionally, by reapplying the same methodology to other popular Firefox browser extensions, we show that these effects are specific to ad blockers. We conclude that ad blocking has a positive impact on user engagement with the Web, suggesting that any costs of using ad blockers to users' browsing experience are largely drowned out by the utility that they offer.

CirnOS is an operating system for the Raspberry Pi built for the purpose of usability and simplicity. It provides a simple environment for running Lua scripts on Raspberry Pi. It has no kernel or time management - it is single threaded. You run your code on the device, and that is it.

CirnOS has only been tested on the Raspberry Pi Zero, but should work on the original Raspberry Pi and the Zero W.