Wikipedia:Reference desk/Archives/Computing/2019 July 16

= July 16 =

Is that Intended?
(After Question at the Teahouse) is [https://en.wikipedia.org/w/index.php?title=Wikipedia:Teahouse&diff=prev&oldid=906439945 this intended by MediaWiki? I mean, you can't really do damage except that you place an overlay over the whole page which prevents the page from being seen (And since that div elements are also transcludeable, you could perform high level trolling if you place this on a template used by System messages or e.g. The main page, if they aren't cascading protected). I guess the only way to fix this is to configure the software behind Wikipedia to remove the "position" attributes from the source code when parsing. However, I'm unsure where to report this. 85.199.71.123 (talk) 06:34, 16 July 2019 (UTC)

Why did my clock stop?
I don't know if this happens every time, but I noticed the last several times when I couldn't use the mouse or the keyboard that the clock wasn't working either. The sign that something is seriously wrong is that the hand won't stop being a hand when I want to type something, or it won't become a hand when I want to click (though at that point it also can't be moved).

I thought my userpage had my computer information on it, but that's my old computer. I am using Windows 10 and Microsoft Edge.— Vchimpanzee  •  talk  •  contributions  •  19:06, 16 July 2019 (UTC)


 * Sounds like the computer is out of resources, like RAM, and needs a reboot to free up some. If only the clock was off, and everything else was fine, I'd say it needs the battery replaced. You might add more RAM, if not already at the max. SinisterLefty (talk) 19:38, 16 July 2019 (UTC)


 * How would being out of resources stop the clock?— Vchimpanzee  •  talk  •  contributions  •  19:45, 16 July 2019 (UTC)


 * It doesn't actually stop the clock, just the update of the display. SinisterLefty (talk) 19:58, 16 July 2019 (UTC)


 * Okay, that makes sense.— Vchimpanzee  •  talk  •  contributions  •  20:06, 16 July 2019 (UTC)


 * How much RAM do you have? Sounds like your computer is freezing up completely and that could have a lot of reasons, most of which have nothing to do with RAM. I'd also bet it has nothing whatsoever to do with the battery, whether CMOS or the laptop power source. If you prefer to throw time and money at it without delving into the problem, I'd suggest installing Windows 7 on another partition as a better investment. Have you done an antivirus check? You could be infected with a cryptominer or be part of a botnet. Visiting crpytominer-infected or ad- and tracking-heavy websites can also cause your computer to freeze; I don't know if Edge has switched to Chromium engine yet but Chromium is pretty bad at handling this and due to its multi-process design it's pretty much impossible to recover the system (short of rebooting) once Chromium freezes it up. Did you recently move your computer case or change a component? This is often a short circuit or airflow problem. It could also be a problem with the drivers for a device you recently added (whether USB or inside the case). 93.136.58.135 (talk) 05:14, 18 July 2019 (UTC)


 * Yes, at this time of the year overheating is a possibility in the Northern hemisphere. Is the room warm ? If so, you may need supplemental cooling for the PC. SinisterLefty (talk) 17:19, 18 July 2019 (UTC)
 * I don't know. How much RAM do I have?


 * There is no laptop, so there's no laptop power source. It is a desktop which plugs into the wall. Eventually. There is a series of three plugs, one of which is plugged into a surge protector. And the wire plugged into that has a plug on the other end, but not metal, which is plugged into whatever is plugged into the back of the computer.


 * Since I have Windows 10, installing Windows 7 doesn't seem like a solution.


 * The antivirus check never finds anything. I do sometimes get messages saying my protection has expired but McAfee told me to ignore those as they don't come from McAfee and they're wrong. I also occasionally get messages saying if I don't call an 800 number everything on my computer will be deleted to protect the rest of the world. But I don't go to risky websites.


 * The computer is in the same place it has always been and nothing has been changed. I get updates periodically and I am told to restart the computer so those will be installed.


 * It is hot here but the air conditioner is next to the computer. It's not always on if I'm not at home, though my heat also cools the house. It's just not turned up very high.15:44, 19 July 2019 (UTC)
 * These 800 number and protection expired messages are scams, usually just scammy ads on websites that you can get rid of with an ad blocker. Are you seeing them when not browsing the web? If so that's probably a problem. 93.136.39.191 (talk) 22:48, 19 July 2019 (UTC)


 * Control Panel + System will tell you how much RAM is available (at least it does for me). You might want to aim the A/C vents directly at the PC, and always have the A/C on when it's in use. Make sure there are air gaps around all sides and top of PC, and especially don't push it up against an exterior wall. SinisterLefty (talk) 15:54, 19 July 2019 (UTC)
 * You'd be surprised how many people like to keep their PC case with the back to the wall (and the back is where all the fans are most of the time). 93.136.39.191 (talk) 22:48, 19 July 2019 (UTC)


 * 10.9.18362, HP 251-a126, Intel J2900, 3.88 GB physical memory, 512 MB available physical memory, 7.68 GB virtual memory, 2.5 GB available virtual memory, 3.8 GB page file space.— Vchimpanzee  •  talk  •  contributions  •  16:57, 19 July 2019 (UTC)


 * Ok, it looks like you have the standard 4 GB (3.88 GB with some overhead subtracted) for that PC, which supports up to 8 GB, with 4 GB in each of the two slots, according to crucial.com. They offer that upgrade kit for US$48: about halfway down this page. I'm guessing that you wouldn't be comfortable installing that yourself, but you may know somebody who is. It does look to me from those stats like you were nearing using up the full 4 GB. I'm not sure how virtual memory differs from page file space, but note that page file space is a much slower form of memory, and I'm guessing the same is true of virtual memory. So, if you want it to run fast, that is, not "lock up" (which is really just running extremely slow), you need enough physical memory. Therefore, you can decide if you can live with it as is, or if you want to try the $48 upgrade. If you decide to live with it as is, try running less stuff at a time, and doing more frequent reboots. That will help. SinisterLefty (talk) 18:24, 19 July 2019 (UTC)


 * Virtual memory is the total memory available which consists of physical memory, page file(s), swap space for system that support swapping, and clean pages that are out on disk (code, unmodified data). In the real world the clean pages are probably insignificant and Winboxes don't swap, so VM = PhysMem + PageFile.  When your program references VM that is not memory resident (ie in PhysMem), the a page fault occurs and the page has to be read from the PageFile and loaded into memory (Paging in) before execution can continue.  If there's not enough free space in PhysMem, then before paging in, something else has to be paged out.  It is this paging activity that slows down accesses from the page file.  To complete the picture: several pages are brought in or out in a single operation to reduce the overheads and systems retain a cache of pages that have been written out but can be recalled at memory speeds if needed.  This latter operation is a soft fault and has a relatively small overhead. HTH, Martin of Sheffield (talk) 20:02, 19 July 2019 (UTC)


 * Thanks for the info. In my experience paging space is bad news. It might in theory only be a little bit slower, but the reality is that once it starts, the PC just can't keep up, so the paging space gets filled up too, then the PC locks up. A better option would be if it popped up a warning and asked you to close some programs as soon as paging gets to a certain (relatively low) level. SinisterLefty (talk) 22:35, 19 July 2019 (UTC)
 * That's probably if the system starts thrashing. Image A wants to run, but because of memory shortages the system needs to page out image B's dirty (ie modified) pages.  The system then pages in A's pages and transfers control to image A.  This has all taken so long that almost imediately the quantum expires and B is scheduled to run.  It can't, because all its dirty pages are in the page file, so A's dirty pages are written and and B's paged in.  B starts to run, and guess what - quantum expires and A is scheduled to run, but it's pages are on disk!  Repeat until the user gets fed up and gives the three finger salute!  The term comes from the days when disks were stand alone cabinets and you could actually see the paging disk thrashing around on the floor. Martin of Sheffield (talk) 10:43, 20 July 2019 (UTC)


 * Yep, that's it. The only way to be certain to avoid that is to have enough physical memory (RAM) so it never gets to that point. SinisterLefty (talk) 17:31, 20 July 2019 (UTC)


 * Okay, thanks. I won't be spending that money. I only had one case today where it felt like things were getting too slow and I closed one thing that I was doing. Extremely slow, as you call it, is when nothing happens when I use the mouse or the keyboard. It's possible something would happen if I waited. I should add that sometimes when this happens I get a high pitched beep for every attempt to click or type. And I'm guessing even that is delayed. There's another lower pitched sound, more like a doorbell, when I try to do something that's not allowed.— Vchimpanzee  •  talk  •  contributions  •  19:24, 19 July 2019 (UTC)
 * Yeah 4GB might be too little for Win 10, you might be running into heavy swapping (as Martin of Sheffield described) which grinds the app that got sent to the swap file pretty much to a halt, as its memory is effectively slowed down to hard drive speed. That's why I suggested Win 7, it runs much better on low-end machines and supports all the programs you use. You might also wanna look into Linux (for example Linux Mint is very user friendly and Q4OS was specifically designed for Windows transplants, and you can test both on a Live CD/USB without needing to install anything), which has security support (Win 7 security support runs out next year altho MS will probably still keep patching big flaws - XP got a fix 3 years after end of life) and more crucially supports older hardware. Win 10 has already dropped some CPUs from the same generation your J2900 is from..


 * Another thing to watch out for: start the software you normally use and then open up the Task Manager and on the Performance tab see where your CPU load settles when the software isn't doing anything. If it's above 25-50% you probably have some bloatware running in the background slowing things down. Also, download SpeedFan or HWMonitor (both are freeware and free of spy/adware) and check CPU speed when you're working, and especially when it starts getting slow. Your fans should be spinning up when CPU load increases, and the CPU shouldn't be hitting >70C temps unless it's consistently at 100% load, if that happens your CPU's factory-applied thermal paste might've dried up and need replacing. Intel CPUs can withstand some very high temps on a practically permanent basis but performance starts to degrade already above 65-70C. 93.136.39.191 (talk) 22:48, 19 July 2019 (UTC)


 * I'm concerned that you only have 512MB of RAM available. Something could be eating up your RAM and CPU - check on that (using Task Manager). I'd bump your memory up to 8GB - IF you have a 64-bit version of Windows.  Bubba73 You talkin' to me? 23:11, 19 July 2019 (UTC)
 * I looked up this computer ( HP 251-a126), and it is a really stripped-down, low-quality computer. Bubba73 You talkin' to me? 23:56, 19 July 2019 (UTC)
 * I know. I saw the price and didn't care. I was looking for quality with my first computer and it cost a lot more. Then it started needing a system restore after every single update, and of course the updates kept happening when the computer realized it wasn't up to date. Time for a new one. And this one has given me lots more trouble than the other one did.— Vchimpanzee  •  talk  •  contributions  •  16:06, 20 July 2019 (UTC)
 * Responding to some other comments: the PC is not near a wall. My chair is against the wall and the table with the keyboard, mouse and monitor are away from the wall, with the computer itself on a stool beside it. McAfee Cloud AV is using a lot of memory and I don't even know what that is. I doubt I need anything with "cloud" in it. I have a lot of memory being used by Windows Explorer (but not that much) but there are some files I'm afraid to delete as I have the only copy of something important that is capable of being copied elsewhere, once I figure out how. The conversion process didn't go so well and I'm looking for another method. CTF Loader uses a lot of memory but not that much. The CPU stays above 50 percent and occasionally get close to 100.—  Vchimpanzee  •  talk  •  contributions  •  16:18, 20 July 2019 (UTC)


 * I can relate to not wanted to spend big bucks for the latest and greatest (I'm actually picking up 3 used PCs for free to rehab on Monday).


 * I suggest turning off automatic updates, then reviewing them and only allowing it to install those you actually want (although they don't make it easy, just calling every update a "CRITICAL SECURITY UPDATE" with no further details).


 * To go along with an under-powered PC you might want to stick with older operating systems. I don't actually suggest changing your O/S now, but when you buy a PC, if you can get an older O/S on it, go for it (unless it's Vista, that is). You might use the Task Manager to kill McAfee Cloud AV, and see if you notice any difference. If it starts up automatically, look for options to disable this within the software. If no luck there, uninstall it.


 * As for using Linux Mint, I have it on one PC, and it works, but there's still a learning curve coming off of Windows. The good thing is, you can boot it up from a USB flash drive, without removing your own Windows O/S. SinisterLefty (talk) 16:54, 20 July 2019 (UTC)
 * Learning to use a new OS would be too much for me, but I'll look into dealing with McAfee Cloud AV.— Vchimpanzee  •  talk  •  contributions  •  16:58, 20 July 2019 (UTC)


 * When running your normal workload, go to Task Manager > Processes and sort them by the CPU column. If you don't have one, go to menu View > Select Columns and add "CPU Usage". This shows the % of CPU load used by each process and should tell you which one is using 50%+. Removing that should solve the CPU hogging part of the problem. It's normal for the CPU to spike immediately when you start Task Manager, but after 2-3 seconds it should come back to a low value if you're not doing anything. Idling above 50% on a 4-core CPU is a sign of something hogging resources.
 * @ SinisterLefty try looking into Q4OS, it has even less of a learning curve, for example it has Windows-like setup process when installing programs. That's probably what I'm switching my main computer to once Win 7 support runs out. I use Q4OS LXDE on an old laptop with 1GB RAM and it's good enough to run 200+ tabs in Pale Moon with a script/ad blocker. It's not that 4GB RAM PCs are underpowered, it's more that Win 10 is an unstable poorly-programmed resource hog ;-) 93.136.57.171 (talk) 21:49, 20 July 2019 (UTC)


 * Interesting. Have you tried Linux Mint, so that you can compare the two ? SinisterLefty (talk) 23:07, 20 July 2019 (UTC)


 * This is a computer similar to yours - start at about 9 minutes in. Ignore what he says about HP meaning "horrible product", because generally they are good.  Bubba73 You talkin' to me? 22:14, 20 July 2019 (UTC)
 * I had good experiences with my first HP. Also, someone at my church works for HP, so it must be a good company.— Vchimpanzee  •  talk  •  contributions  •  17:23, 21 July 2019 (UTC)


 * I just went to my task manager and Cloud AV is not using a lot of the memory now. I haven't done anything that I know of.— Vchimpanzee  •  talk  •  contributions  •  17:34, 21 July 2019 (UTC)


 * It may periodically "back up data to the cloud". If so, you might want to figure out how to set it to do that when you're not using the PC, although presumably the PC would need to be left on. SinisterLefty (talk) 19:52, 21 July 2019 (UTC)

Greek "mu" letters
Hello, what's the difference between these two page titles? They're visually identical, but the full URLs are different: If I strip out everything but the μ character for each, both of them go to Μ, URL https://en.wikipedia.org/w/index.php?title=%CE%9C&redirect=no. It's as if there are two different Unicode characters for the same lowercase "mu" that resolve to the same capital letter, which doesn't make sense to me; we don't have separate characters for lowercase Latin letters (e.g. and ). So apparently I'm missing something somewhere. Nyttend (talk) 23:21, 16 July 2019 (UTC)
 * Sheridan, WY, µSA
 * Sheridan, WY, μSA
 * https://en.wikipedia.org/wiki/Sheridan,_WY,_%C2%B5SA
 * https://en.wikipedia.org/wiki/Sheridan,_WY,_%CE%BCSA
 * I don't have the details at hand, but the general idea was that the folks that invented Unicode felt a need for &mu; used as an ordinary Greek letter, &mu; used as a mathematical symbol, and &mu; used as a unit of measure. The unit of measure was known as the micron, and now the micrometer, &mu;m, is used; they are the same length. See Mu (letter). Jc3s5h (talk) 23:54, 16 July 2019 (UTC)
 * %C2%B5 is the UTF-8 encoding for Unicode Character 'MICRO SIGN' (U+00B5) while %CE%BC is the UTF-8 encoding for Unicode Character 'GREEK SMALL LETTER MU' (U+03BC). Per the linked pages, the suggested uppercase mapping for both is Unicode Character 'GREEK CAPITAL LETTER MU' (U+039C). The micro sign is part of the Latin-1 Supplement (Unicode block) which was derived from the upper end of the ISO/IEC 8859-1 character set. I expect that when the Greek and Coptic group was defined, the decision was purposely made not to omit those characters duplicated elsewhere. -- 02:39, 17 July 2019 (UTC)