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Comment Re: Crackberry is Back (Score 1) 132

It's not self-evident. There are serious jank problems while scrolling, 10-second latency problems navigating trivial apps like Settings, and nagging battery-drain problems with Android. These are the main problems the platform has.

Utter bollocks. And even if it were true (and it isn't) it does not mean the kernel is to blame so your point would still be bollocks.

Memory use isn't one of the problems: the standard phone went from 0.5GByte to 2GByte RAM a couple years ago without any significant change in app functionality, and the K release used less memory than the J release so general platform bloat is actually going backwards: the stack's memory tax is therefore less than a quarter of the standard platform size and not a big deal for emulation.

Utter bollocks again. Android has increased memory generally so more apps stay resident in memory. The less memory, the more likely it would be to purge apps. In other words it makes use of the memory for stuff.

Performance probably isn't a problem wrt the emulation because the performance problems are not flat-out CPU bound work nor mean-latency problems: doubling the mean latency would not be a big deal because android has such huge tail-latency problems. And doubling mean latency in return for cutting max latency is exactly what hard-realtime kernels like Neutrino are made for. Whether they can do this through the android stack is doubtful because the latency is probably coming from java crappo, but who knows. Anyway it's not self-evident that emulation will cause a memory problem for Android, nor that it will cause a performance/battery problem.

Utter bollocks because it presupposes your other bollocks and makes no sense in any event. The point I was making was that to emulate Android, a Black Berry device has the memory pressure of two runtimes in memory at once (the native one) and the emulated one (plus shims). It obviously impacts on memory and performance.

Emulation and battery-drain problems aren't related because they're caused by poor scheduling, bugs, held "wake locks", etc. Part of the area where bugs can exist will be replaced, so if QNX is higher-quality than Android in this replaced area it will win the battery game.

It's true that a misbehaved app can drain battery but normal drain is caused by the screen, radio and general activity. And in any event it's largely an irrelevance what kernel is underneath because an app can misbehave over any kernel. And modern kernels are wasting CPU / battery unless something above is telling them to.

Comment Re: Crackberry is Back (Score 2) 132

It's largely a matter of indifference to a handset's performance what kernel is running under a phone handset. Providing the kernel offers functionality required by handsets it could be NT, Linux, BSD or something else. It's the user land and application sitting on top which dictates the user experience and what hardware / battery the device which dictates that. I assume that Blackberry pack a big battery, the smaller screen and some aggressive power saving defaults could extend the life of the device.

It should also be self evident that if a Blackberry device has to load up a substantial chunk of an Android runtime and an emulation layer (in addition to its own services) to run an Android app that it will be neither as performant or memory efficient as a standard Android device. It has two stacks to wrangle and there might be limits on the Android emulation that cause performance issues of its own.

In fact it's hard to see why they bother emulating Android at all when they could just *be* Android. Doesn't stopping them locking it down with Knox, encrypted storage etc. It would save them a hell of a lot of effort in the long run and would broaden the appeal of a device if it actually ran the apps people wanted to use. Emulation and Amazon's store is better than nothing but it's still an extremely poor substitute for the Play store.

Comment Re:Riiiiight. (Score 1) 233

I have no trouble running a Windows 7 desktop for months without a reboot. Typically I'll work all day and sleep it at night. That's a desktop which is hammering resources for most of the day. Some poxy media system is not going to trouble a kernel even assuming the kernel leaked (which I doubt any modern kernel does).

Comment Re:Riiiiight. (Score 1) 233

It does sound like an advertising pitch, but this is accurate about QNX. The OS isn't cheap, but it does offer realtime functionality. It also is designed to be quite stable to where a bug or a hang can cause tremendous disasters, be it software with X-ray machine or figuring out what position to move a set of control rods in a reactor. QNX has excellent internal security, and a decent development kit.

The thing is here it's being used for an in-car entertainment system. It doesn't have to be realtime, it doesn't have to require stability beyond what a regular kernel would offer. In fact it shouldn't matter a damn what kernel is powering the system since most of the functionality is going to be sitting in an application layer well above the kernel itself.

I'm not sure what motivated Ford to switch. Maybe QNX uses less memory or is more performant with the chipset they want to use, or is simply cheaper to licence. Or maybe the automotive industry is naturally conservative and comforted by some extra certification QNX offers that Windows doesn't. Whatever the reason, I doubt the end user experience or reliability would be appreciably different whether they had used an NT, Linux, BSD or a QNX kernel - any modern kernel would have served the software well. Whether the application itself is good is an entirely separate matter altogether.

Comment Re:dropped that fool and the systemd it rode in on (Score 1) 106

I'm not saying it's hard but it's still has usability that's all over the place. A done button in the top left, an install in the bottom right, where's cancel? The post install welcome screen puts its buttons in the top right! And it's not clear the tasks are actually clickable since they don't look like things to be clicked on (a slight background might help). Another confusion is the exclamation mark sometimes means "you must do something" and other times "you might do something" e.g. I must set my partition but during installation I don't have to create a user, or rather if I change the root password, the exclamation point disappears from add user task.

It's not insurmountable. It's just a bad first impression.

Comment Re:JPEG2000 replaced JPEG (Score 2) 377

A bigger roadblock might be that these days, bandwidth (and storage) is cheap, and so savings in image size are less relevant than they used to be.

Bandwidth isn't cheap on mobile data networks. On the other hand, requiring phones to execute battery sapping image decompression in Javascript is hardly a great idea either.

Comment Re:Remember guys... (Score 1) 73

NOBODY should want Mantle until it becomes an open standard or something analogous to it appears in the likes of OpenGL. It's great that it offers performance improvements but proprietary APIs still stink. I expect most of the improvements it offers largely boil down to minimize the amount of memory being copied around between CPU and GPU rather than anything inherent to the chipset.

Comment Re:dropped that fool and the systemd it rode in on (Score 2) 106

I hate the Fedora installer. I can see what its trying to do but the usability is all over the place. It's not a wizard, the buttons are in unconventional positions, and oftentimes it is unclear whether you have applied things or not because there is a substantial delay between doing something and it reflecting in the UI.

Once its installed and running it's fine though.

Comment My experiences of Android Studio (Score 4, Insightful) 115

I've used Eclipse extensively and I've used Android Studio extensively. So far I have mixed impressions of Android Studio.

In its favour the Android integration is far better - obviously. Android Studio provides all of the tools out of the box to build an Android app from end to end which includes all the packaging and signing at the end. In Eclipse you can can develop and debug easily enough but if you want an apk you have to manually invoke a dialog to package and sign APK. This is a huge pain.

Note that AS doesn't actually build anything. Everything is farmed out to a gradle script. This means you can build from AS, or the command line or even from Jenkins from the same script. This is very useful and you can your own custom tasks, unit tests and other goodness to your scripts. But... gradle is goddamned slow. As in REALLY slow. Even if you configure it spawn a daemon so it doesn't respawn all the time (yes I've done that) it's still slow. The problem is if you change a Java class it still has to run through every task checking the dependencies to see what needs to be built and it takes too damned long.

Eclipse is extremely good at incremental building so you can make a change and hit run and in seconds you're debugging. Eclipse is also superior for marking code in error - AS only tends to know about errors local to the file, e.g. syntax errors. If you call a method in another class and get the params wrong you might only be told when gradle reports an error. In Eclipse it would have told you instantly which means turnaround is so much faster. I also prefer the Java editor in Eclipse, because it knows more about your project as a whole, the code completion and hints are more immediate and useful. I'm also used to the keybindings but AS has some Eclipse keybindings so that doesn't matter too much.

Android Studio does have some excellent code analysis tools. It has Android lint integrated into the build and there are a pile of things it can search for in addition to that and in many cases will offer automatic solutions. It also has nicely integrated view and fragment editors which work better than the ones in Eclipse.

AS is a terrible CPU hog. I've noticed it eating anywhere between 5-30% of the CPU depending on what panes are open. This is a serious problem on a laptop because the fan starts whirring and the battery life suffers. The command prompt pane is the worst of all and I only assume it's killing the CPU by continuously polling. Source code integration is also inferior to Eclipse - EGit is a wonderfully mature plugin these days with some complex and useful functionality - the support for Git in AS seems quite perfunctory by comparison although it covers the basics.

So to summarise pros for AS:

  1. End to end builds for Android apps
  2. More integration for Android tools
  3. Excellent code analysis
  4. External build system making it easier to do custom tasks and automated builds.

And the cons:

  1. Gradle really sucks for iterative development and slows things down. It's also a massive learning curve.
  2. AS is a CPU hog
  3. Source control integration is weaker
  4. If you have a mixed development environment (e.g. client and server side components) or multiple targets then an Android-centric IDE might not be so good as Eclipse.

Comment Re:Sadly,... (Score 1) 180

Because it's not like anyone's ever been raped by a 'licensed and regulated' taxi driver.

Well that's genius logic. Your link demonstrates the need for an even higher standard for background checks and a zero tolerance for drivers with convictions that could be a threat to the public. In this instance it would suggest that the decision should not have been entrusted to the council in the first place - they should be responsible for the paperwork but the police should ensure the driver is of good character and their say should be final.

It also does NOT suggest that we should loosen or do away background checks altogether so that any psychopath, even those with previous convictions, can lure women into their vehicles.

I'd add that if you were to search for high number of court cases involving unlicensed cab drivers (i.e. those illegally operating taxis), that it demonstrates why checks are so necessary in the first place. Not just on the driver, but also the state of the vehicle they are driving in to ensure it is roadworthy and insured.

Further, I'd note that there is no reason that Uber cannot operate within the law. They can require their drivers hold a taxi licence and be in good standing. They just choose not to because interferes with their profits.

Comment Re:Entrapping idiot with dubious plot (Score 1) 388

I was watching an episode of the BBC drama series "Colditz" the other day. One of the POWs attempted to bribe a German guard who needed a lot of money (his girlfriend needed an abortion). Rather than take the bribe he reported it and the chief security officer rewarded him with 2 weeks leave and a posting to somewhere closer to his family. Smart when you think about it - you want to encourage people to report events that could compromise security, not make them fear that they'll be punished.

The TV series is fascinating viewing especially from a security perspective since its informed by real events and contains many parallels for modern day security practices.

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