Thursday, October 27, 2016

YouTube video stuttering in Firefox

This post concerns a relatively specific hardware and software setup.

I have a nine-year-old computer that has just 1 Gb of RAM (yes, one gigabyte), a one-core CPU and an integrated Intel video adapter. The operating system is Windows XP SP3.

In that computer, the default browser is Firefox because of its much lower memory footprint compared to other major browsers; and the version of Firefox is 39.0.3, as it's the last one with which Flash videos (off YouTube) are played back without stuttering much. That older version of Firefox also supports cookie prompts, which were removed in Firefox 44 or 45.

For that non-stutter to happen, I must set the process priority Above Normal for Firefox's plugin-container.exe program in Process Explorer (the latter is a fancy task manager; I usually have it on all the time).

So far, all this has worked nicely with Flash extended support releases (ESRs, currently at 18.x.x.x branch) up until version 18.0.0.266; I haven't tested with newer Flash versions yet.

Caveat: This setup didn't seem to work properly on a newer computer with the same OS and more RAM (wherein Flash stuttering in Firefox was much lesser, btw), apparently causing slowdowns with heavy CPU usage and other issues. I never quite found out what the exact cause was, but upping plugin-container priority might have been it.

IIRC, Linux seems to have that stuttering issue solved with Firefox and HTML5 video playback and a fresh profile. At least I don't remember any stuttering issues in Linux.
Strangely enough, resource usage scenarios are different between Windows and Flash vis-a-vis Linux an HTML5: In Linux, HTML5 video playback does not seem to consume a lot of resources on its own; whereas HTML5 video playback with the aforementioned Windows configuration is very resource-intensive, while Flash playback is reasonable in terms of CPU usage.
Other settings of note that decrease Firefox memory/CPU consumption:
(There's an older blogpost that I've considered updating. Might as well put all this into a completely new post to reflect the times, since many long years have passed in-between.)
In about:config

browser.sessionstore.interval is set to 600000. This interval changes the frequency of session saves.
browser.sessionhistory.max_entries (current browsing history per tab) is set to 25 instead of 50.
browser.sessionhistory.max_total_viewers is set to 0.
nglayout.initialpaint.delay is set to 0. The default non-zero value allows the Gecko layout engine to wait a while until a major part of a page is loaded. The setting of 0 can be more CPU-intensive, but I sometimes prefer seeing a complex page load early.
For very long and complex pages that might choke a graphical browser, there's Lynx.
Most of the plugins (not browser add-ons, but actual plugins) are switched off or set to Ask to Activate.

NoScript, Flashblock and Adblock Plus (ABP) are the must-have extensions for Firefox, without which normal web browsing would be impossible.

For many years, I didn't even use an adblocker, and entirely relied on NoScript and Flashblock, but video ads on YouTube had finally caused me to install ABP.
I recall this was gradual, and I used to use only Flashblock, but then having to use older Internet-connected computers (around 2010/2011 or even a couple years earlier), I finally resorted to using NoScript, too.
Since Firefox and SeaMonkey share the same rendering engine, these settings and add-ons apply to both.

On my currently-primary Firefox profile, I also keep the same session for many months, with lots of tabs that could instead be saved into bookmarks, but Firefox is set only to open the tabs that I select at startup.

The PlacesCleaner add-on can occasionally be used clean up the session database that's become a bit messy over all those months. In time, I'll transition to a new profile, so that I'd be able to do some work and stuff and keep the bookmarks. And it's likely, that with this Firefox profile, I won't be saving the session, and will use bookmarks instead for all the stuff I want to read later on.

Sunday, October 23, 2016

Galaxy Note 7 and possible causes of fires

When thinking about the possible reasons why Samsung Galaxy Note 7 became flammable, I asked myself several questions: Can a magnet affect a phone battery? Are there magnets in the S Pen — the stylus that comes with the phone and that stays inside the phone case when not in use? Were users with phones that burned, using leather holsters with magnets (as many people do with other phones do)?

As a disclaimer: This blogpost is pure speculation rife with theories and hypotheses unconfirmed by hard facts (scientific or otherwise), much of which is original research. Neither do I know very much about how smartphone screens are made, and my knowledge of chemistry and physics is lacking. Many of the claims are qualified with terms, such as "likely", "possible", "probable", and so on. The intention of the post is to ruminate over what caused the fires, since finding the cause would be in the best interests of Samsung, other smartphone makers, and the public at large. In addition, I'm a user of two Samsung phones, one of which is a smartphone.


I began looking for news articles about Samsung Galaxy Note 7 and magnets, and came across this one from August 22, 2016 published by Korea Joongang Daily:
"Samsung’s Galaxy Note 7 is marvel of waterproofing".

The article explains, that:
The Note 7 and its S-Pen can work under water, because the phone's LCD and the S-pen respond to one another through a magnetic field in much the same way pieces of iron move in the direction of a magnet, when said magnet and iron pieces are separated by paper.
Further:
Even with water between the display and the S-Pen, the device "recognizes and responds to the S-Pen’s magnetic field."

My conclusion is,

that the phone battery was susceptible to magnetism, because it wasn't sufficiently protected from magnetism inside the phone, where the S-Pen was housed. The additional reason could be, that the internal phone battery, apart from some plastic, seemed (according to teardown photos) to lack any other protective material to shield it from magnetism.

All this suggests, that the Note 7's LCD is a magnet, and the S-Pen is, too, and the battery in the phone is still about the same in terms of its own housing as used in earlier models.

This is based on the assumption, that the housing of this kind of internal battery has not changed much from earlier internal Galaxy Note and Galaxy S batteries. The fact, that batteries with similar housing didn't combust in earlier Galaxy models, was because magnets (or magnetism) were not used in the screen and the new S-Pen.

The possible design mistake in the Note 7 is, that the engineers probably forgot to account for the fact, that the battery, with its usual housing, was susceptible to magnetism that emanated from the phone's screen and the S-Pen, either during use or when idle.

Samsung won't refurbish the recalled devices, and won't reuse its components.

Whether the magnetic screen and the magnetic S-Pen are the reasons for fires in the batteries, is unknown. Whether Samsung is currently aware of these as the underlying issue(s), is also unknown. And if it is, the public should know when the company first realised this.

If I were a mobile phone manufacturer, and realised, that the magnetic screen and stylus were affecting the batteries, then as a matter of business, I would halt production of this model of device, and choose not to refurbish or reuse the magnetic screen and pen that would adversely affect any normal battery that's close by.

The most widespread photos of exploded Note 7 models show, that it was the screens that burned through the most, but not the backsides of the poor phones. Investigating the burned phones for the direction of the burns and fires should confirm this. Granted, the backsides of the phones were made of metal and other materials that were stronger than the screens, and explosions and fires would move towards the area that would first give way.

Another interesting thing that the photos of burned Note 7 phones show, is that the screens burned through completely at the location of the batteries. Part of this burn-through could be attributed to extreme heat from the burning batteries, but I'd imagine, that the displays, made of mostly glass, would stay intact.

I do not know, whether it was the S-Pen, or the screen, or both that were ultimately culpable for affecting the batteries.

No issues were probably found in testing, because the effect of the magnets was not immediate.

I can imagine, that both the phone and the S-Pen were developed by separate teams, and I think it inconceivable, that the S-Pen was never inside the phone during testing, or that they were not tested in conjunction.

The U.S. Consumer Product Safety Commission would be very smart to subpoena the carriers and Samsung for lots of Note 7 devices (not just tens, but more) to find out independently what went wrong.

In addition, The Times of Malta reported, that "a team scientists at New York University led by Alexej Jerschow, developed a magnetic resonance imaging (MRI) technique to see inside the batteries as they are charging."

This new method could be used at the behest of the U.S. Consumer Product Safety Commission to investigate the extant Galaxy Note 7 devices—both original ones, and replacements. Care should be taken with the fact, that the screen and the S-Pen of Galaxy Note 7 phones are themselves magnetic.

Saturday, October 8, 2016

Windows: Creating a shortcut to select a file in a folder

I often need to find out which version of Skype installer was automatically downloaded into the local temp folder.

While the Windows UI makes it possible to create simple shortcuts, then there is no UI for more complex stuff.

After some searching, the correct Target line in the shortcut properties must be this:

C:\WINDOWS\explorer.exe ,/select="C:\Documents and Settings\A User's Account Name\Local Settings\temp\SkypeSetup.exe"

It is important to separate the executive and its options from each other with a space, after which the comma starts in that line.

This also works from the command prompt.

Applies to Windows XP, but should also work in other Windows versions. YMMV.