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How long ago did you last assemble a computer?

arth1 Re:On more thing - cases are so much better (259 comments)

That's not due to better design, but more use of cheaper and softer materials. They're not built to last anymore. Give me a 10 year old Lian-Li case and band-aids any day over today's cheap plastic.


X.Org Server 1.16 Brings XWayland, GLAMOR, Systemd Integration

arth1 Re:Systemd? Not on my system... (226 comments)

You just claimed your SysV init scripts are helping your software take advantage of cgroups.

If that's what you read, you need to practice your reading skills, cause they suck.
What I pointed out is that cgroups are separate from the init process, and can and do indeed run on sysv init systems too. cgroups has nothing to do with init, and runs separate from init no matter what you use for init.

When you brought up cgroups as an argument, it appeared to be from a false belief that systemd was needed for cgroups to work - in fact, it's the other way around!
And when systemd uses cgroups, it takes them over for its own purpose, which lessens the value of cgroups compared to systems where you are free to use cgroups from scratch. Freedom to choose - that's what makes Unix great. Poetterware takes away that freedom.

about two weeks ago

X.Org Server 1.16 Brings XWayland, GLAMOR, Systemd Integration

arth1 Re:Systemd? Not on my system... (226 comments)

TCP isn't noticably more secure than UDP - the extra fields in TCP are unsigned and can be spoofed too. There are even a couple of attacks that only works with TCP, like source congestion. The only "security" TCP buys you is if you have a dynamic real-time alerting system for tcp sequence errors and similar likely to be seen in spoof attacks. You don't have such an alerting system.
Thus, security is implemented on top of the transport layer, where it works just as well for udp as tcp. The advantage of udp then is that you get more payload per encrypted or signed unit, thus higher speed.

That said, the main use of nfs is within secure perimeters, where speed and transparency is the main goal. In which case all you need is a honor system access control, designed to prevent users and apps from doing bad things no matter who they (say they) are. I.e. the focus is on what is shared, and what's allowed, not who you share it to.

Where Windows is very user focused in its trust based security model, Unix is very data focused.
A typical Windows share will allow any user to write and execute whatever they like. The users don't understand the "Advanced Security" properties anyhow, so implementing it will just lead to complaints. If a client is compromised, so is the share..
A typical Unix share will only allow users write and execute access to specific directories, no matter who they say they are. Remote root users typically get even less access, not for security but to prevent accidents. If a client is compromised, the shares should be safe.

about two weeks ago

X.Org Server 1.16 Brings XWayland, GLAMOR, Systemd Integration

arth1 Re:Systemd? Not on my system... (226 comments)

NFS is crap too and in my testing also slower.

But nfs does not take over and cripple your dns server.
It's the hooks into and taking over parts that work fine on their own that's the problem with domain controllers and systemd. It goes directly against the Unix toolbox approach, and stifles innovation because now you have to do everything within the context of the super-program.

(As for your testing, did you try with jumbo packets? NFS supports it, and CIFS doesn't. It makes a tremendous difference, especially for writes to remote RAIDs or disks with a 4k block size. Also, avoid distros that set up NFS to use tcp instead of the default udp. That's a huge performance killer, and not needed unless you use hubs instead of switches or need to tunnel the traffic.)

about two weeks ago

X.Org Server 1.16 Brings XWayland, GLAMOR, Systemd Integration

arth1 Re:Systemd? Not on my system... (226 comments)

Are you insulting the samba project ?

No, not at all. They produce the very finest shit eating utensils in the world. It's not the utensil that is the problem.

about two weeks ago

X.Org Server 1.16 Brings XWayland, GLAMOR, Systemd Integration

arth1 Re:Systemd? Not on my system... (226 comments)

cgroups reduces overall system complexity by providing a means of managing process groups. cgroups are a new feature in the linux kernel. It exists for real reasons. I guess you think it would reduce complexity and keep it simple to just tack on cgroups to what SysV init already did, right?

What does cgroup have to do with anything? I run several systems with cgroup and sysv init. The two are separate, and there is no need for systemd for that.

None of your complaints are actual problems with systemd. It is just repeated propaganda.

Actually, they're all mine - no repeat at all. I have been a system administrator since the early 90s, and know what problems Unix like systems have. sysv init has not been anywhere near the top of that list. It was a great improvement over starting apps directly from inittab, and is something that has been working and has kept on working, precisely because it's so simple.

I guess you'd have to resort to comparisons that claim that SysV is even easier than DOS, because learning bash scripting and the standard SysV sh libraries is so much easier than learning that an .ini file has sections.

I say this with feeling: You are an idiot.
The problem is obviously not "learning that an .ini file has sections", but that you cannot easily use standard Unix tools on an .ini file because of the sections. sed -e 's/port=.*/port=587/' works great on standard config files, but not .ini files where more than one section may have a port. .ini files are inherently automation unfriendly, because the lines depend on a context you can't derive from the line itself.

about two weeks ago

CCP Games Explains Why Virtual Reality First Person Shooters Still Don't Work

arth1 Re:barf (154 comments)

I get seasickness from some fps games. Strange enough I always get them from console FPS games. Only sometimes from PC FPS games. Maybe it's the framerate?

No, more the rubberbanding. Consoles don't have mice that can easily change acceleration and start and stop instantly, so to make games playable with a controller, the movements are not synchronized with the stick - when you let go of the stick, you don't instantlly stop, but your movement slows down to a halt over a small period of time. So your actions don't match your movements.
That's also seen in bad console ports, by the way.

about two weeks ago

CCP Games Explains Why Virtual Reality First Person Shooters Still Don't Work

arth1 Re:Not if you use the Virtuix Omni (154 comments)

That depends on whether the sickness is caused by the lack of leg movement or not. It think there's a good chance the problem is tied to the inner ear (or more precisely your sense of movement vs. visual feedback), or possibly something else, in which case a treadmill might not help at all.

Indeed - the Virtuex Omni is more likely to make things worse. Your eyes say one thing, your feet another[*], and your inner ear disagrees with the two.

Think about it - when you drive a car, you don't have to move your feet like a mad runner in order to avoid feeling sick. Your inner ear gets the cues from the accelerations, and those match what you see, as long as you look out the windows. If, on the other hand, you're a kid that reads or play in the back seat, your visual cues don't match your inner ear, and you may get sick. No matter what your feet do.

[*]: Unless adjusted so 1 m in the game is exactly 1 m on the treadmill, and unless you only move on flat surfaces, it is safe to say that your legs will disagree with your eyes.

about two weeks ago

MIT May Have Just Solved All Your Data Center Network Lag Issues

arth1 Re:Ugh... (83 comments)

They may slow down the world if this gets hyped to the point that it sells.
The problem is T.ANSTAAFL. This is Yet Another Implementation that seeks to reduce the average latency, without thought to the fact that what really hurts is the worst case latency bottleneck. This, like many other approaches before it, will worsen the worst case in order to buy the average case lunch.
You either have to come up with a solution that reduces the worst case, which is what really hurts, or make Pareto improvements, i.e. those that hurts no-one, even in corner cases.

This is not it. And yes, I have looked at it.

about two weeks ago

X.Org Server 1.16 Brings XWayland, GLAMOR, Systemd Integration

arth1 Re:Systemd? Not on my system... (226 comments)

If they were in released software, well, it is normal that SysV get replaced eventually

I guess that depends on your definition of eventually. Good working designs don't have to be replaced any time soon.

We still have steering wheels on cars, despite some people in the 70s thought that joysticks and hand controlled throttles would be much better. Most of my clothes have buttons, despite Velcro and Ziploc. Heck, even zippers did not replace buttons.
Change for the change of change is seldom a recipe for success. The number of admins who complained about sysv init and not having an octopus program with hooks into everything were not really high. In fact, most admins have praised the toolbox approach where mounting is a completely separate thing from starting a daemon, and where nothing is truly integrated but everything is as separate as possible. The Unix mantra is "do just one thing but do it well".
I don't really care whether systemd shaves twenty seconds off the boot. My systems run for years, and take ten or more minutes from power-up doing hardware checks and RAID enumerations until they even start booting. That the boot process isn't abstracted and can be troubleshot by a human is far more important. So is the ability to easily have different systems with the same installation base do different things. Or make changes that you know won't take effect immediately. Or replace one thing without replacing ten more. Or use config files that you can do a simple search/replace on, unlike MSDOS .ini files where you have to be aware of the "section" abstraction.
K.I.S.S., and avoid abstractions like the plague it is.

about two weeks ago

X.Org Server 1.16 Brings XWayland, GLAMOR, Systemd Integration

arth1 Re:Systemd? Not on my system... (226 comments)

No, generally emacs users are happy with systems that have both emacs and vi, and emacs won't prevent vi (and all the tools depending on ex/ed) from working.
This is more like replacing ISC bind with samba domain controller. It's incomplete, broken by design, and has so many levels of abstractions that no sane person can admin it without specialized tools.

I'm already boycotting Red Hat 7 because of the poetterification that changes simple things that work to complex things that don't. Now Xorg will have to go too.

about two weeks ago

Public To Vote On Names For Exoplanets

arth1 Re:Crikey (127 comments)

There already is a generator.
Expect the first planet to be named Lave, and be famous for its vast rain forests and Laveian tree grub.

about three weeks ago

Predicting a Future Free of Dollar Bills

arth1 Re:Cashless can't happen, here is why ... (753 comments)

The ONLY thing required for this to happen is secure communications.

That's like saying "the ONLY thing required is world peace".
What admins and engineers have known for a long time, and which people like Snowden provided evidence for is that secure communication is not a given, and highly unlikely to be an option for the masses.

If the government won't let people have a shadow economy they can't monitor or control, expect physical alternatives to take their place. There's plenty of precedence for turning to valuable metals when the currency cannot be trusted. And there are examples of governments banning both gold and silver trade as a kneejerk reaction, but that just moves the market to something else.

about three weeks ago

My most recent energy-saving bulbs last ...

arth1 Re:LEDs (278 comments)

I'm switching out my lightbulbs - to halogen lights.
I can't stand the visible flickering of LED lights, nor that they don't light in a continuous spectrum. Some colors will show stronger and some less in LED light, which irritates me.
It's like listening to music with an 18-band equalizer, and three random knobs turned all the way up, and the rest down.

Halogen lights don't have that problem, and you can get them in many color temperatures. They're far more efficient than regular incandescent bulbs, while still having the advantages of an unbroken spectrum and little flickering. They're also safer for the environment to dispose of than LEDs.

about three weeks ago

Avast Buys 20 Used Phones, Recovers 40,000 Deleted Photos

arth1 Re:Garbage In (231 comments)

Out of the 2 Android phones that I have had, zero of them came with Facebook preinstalled. I blame the mobile phone provider.

Your blame is at least partially misplaced. Manufacturers also bundle software, regardless of the carrier. The last two Android phones I had were bought directly from the manufacturer as never-locked phones (not to be confused with unlocked, which means the carrier lock has been removed). Yet there still was plenty of bundled and uninstallable software, including Facebook, Twitter, Google+, Drive, Hangout and Picasa apps and integration for pretty much everything. I have disabled more than 20 bundled apps.

The manufacturer assumes that everyone uses the big social media sites and want to tell their friends (and their friends) about everything they do, including what music (or audio books) they play, what pictures they take, and where they currently are.

It's good that social exhibitionism became acceptable (thanks to Jennifer Ringley more than anyone), but that it became the norm to the point that it's bundled is something I strongly object to. It's like buying a toilet and finding out that it (unadvertised) comes with wan connected crotch cams that can't be removed, just temporarily disabled.

about three weeks ago

Utility Wants $17,500 Refund After Failure To Scrub Negative Search Results

arth1 Re:You can polish a turd. (110 comments)

... we're having Peking Witch for dinner?

about three weeks ago

Lyft's New York Launch Halted By Restraining Order

arth1 Re:Why are the number of cabs [artificially] limit (92 comments)

It's rather the opposite. When people take a cab, they don't take a car, and won't spend time driving around looking for a parking space.
Having enough taxicabs also reduces the amount of drink driving, which is a serious problem here in the US.
And you free up parking lots and parking garages, which can be used for other infrastructure, which reduces the need to travel even more.

I've lived in cities with plenty of taxis, and I've lived in cities with next to none. The cities that had a surplus of taxis also had the least amount of traffic problems.
London has around twice as many taxicabs as New York City, for a comparable population size. Other European cities have an even higher ratio of taxis per citizens, with a 1:100 ratio not being uncommon. And those cities have the least amount of problems with automobile traffic too.

about three weeks ago

Ode To Sound Blaster: Are Discrete Audio Cards Still Worth the Investment?

arth1 Re:USB DACs (502 comments)

No, optical spdif to a dedicated receiver.

Why optical? You introduce two extra conversions which are possible causes of error and adds a small amount of latency. Copper S/PDIF works better, and the cable won't break if you bend it or step on it.

about three weeks ago

Child Thought To Be Cured of HIV Relapses, Tests Positive Again

arth1 Re:I hate to imagine it (126 comments)

If the reinfection is also from the mother (which is what is most likely)

How can you say that is most likely?
HIV does not spread easily. The panic times when people wore gloves and masks around the HIV infected are long gone, thankfully. The HIV virus spreading to family members is quite rare.
Diseases staying dormant for a long time is, however, not unusual at all.
So again, on what basis do you draw the conclusion that a re-infection is most likely?

about three weeks ago

The Pentagon's $399 Billion Plane To Nowhere

arth1 Re:And Joe Schmoe wont care. (364 comments)

Half our registered voters don't even want to pay for healthcare for our citizens, why do you think we would pay for this?

I haven't met many fellow Americans who are willing to pay for healthcare for anyone. Half of them are willing to subsidize private health insurance, which is still a right-wing approach seen from a world perspective.

It seems like another way to move money from the middle class to corporations, giving the lower income workers extra expenses they can ill afford, even subsidized. It doesn't help to have health insurance if you cannot afford the co-pay and OOP expenses.

The very idea of funding healthcare directly, not going through private insurance intermediates who milk the maximum amount of money from both sides, is one that seems alien to Americans, no matter what party they claim to support.

about three weeks ago



Blog pioneer WELL close to closing

arth1 arth1 writes  |  about 2 years ago

arth1 (260657) writes "One of the first Internet communities outside Usenet, The WELL (Whole Earth 'Lectronic Link) is in dire waters. The owners, Salon, have laid off the entire staff, and are looking for buyers.

The WELL started out as a BBS-like entity, and proceeded through telnet to also support web and e-mail. Its web interface may seem dated by today's standards, but it works quite WELL, and was an influence on many later online communities, including Slashdot.

Subscribers received an e-mail from Salon Media Group's CEO Cindy Jeffers, stating:
"[....]as part of the company’s review of its strategic objectives, we have determined that The WELL no longer aligns with our business plans and accordingly we are exploring transferring The WELL to new management."

This came as a surprise to the employees. Gail Williams, one of the (former) employees wrote in a newsletter:

"On May 30, 2012, the community department at Salon was disbanded, and the three employees who had been working from 30% to 100% on running The WELL were laid off. We were shocked, of course."

Now is the time to make an offer to save this historic landmark on the Internet."

Link to Original Source

arth1 arth1 writes  |  more than 7 years ago

arth1 (260657) writes "From the Bay City news wire:

"A friend of Nina Reiser, an Oakland woman police believe was murdered, has helped set up an education fund for her two young children.

Ellen Doren said people who want to contribute to the fund should make out checks to "Education Fund for Rory and Nio Reiser" and send them to Education Fund for Rory and Nio Reiser, 6114 LaSalle Ave #127,Oakland, CA 94611."

Sounds like a good idea; orphan kids are stuff that matter."



Letter frequencies in URLs

arth1 arth1 writes  |  about a year ago

Doing some maintenance on a few squid cache servers, I decided to look into the letter frequency distributions for URLs, and how it matches normal written text.
Four caches were scanned for the URLs of currently cached content only, constituting around 1.5 million URLs.

In short, the results have some of the same characteristics as normal text, but with notable exceptions. You don't get an etaoin shrdlu; there are a lot of h, t, p, colons and slashes in URLs which skew the results. I'm also surprised that w scored so low, given all the URLs that start with www.

If anyone else finds a use for this, here is the data. Each character in the URL is followed by the number of times it was used in each cache, plus the total for all four caches.

/: 83198 130244 3028097 2929538 6171077
t: 73026 99729 2727455 2641930 5542140
e: 52801 95537 1746624 1753865 3648827
.: 35317 60175 1478231 1467006 3040729
o: 40941 86873 1423124 1448453 2999391
a: 43075 72450 1408451 1384211 2908187
c: 36078 64921 1308435 1295986 2705420
s: 41946 76684 1251987 1278493 2649110
p: 28248 44907 1214805 1190698 2478658
m: 29609 45768 1168769 1195505 2439651
h: 22543 41992 1029463 1019494 2113492
i: 37846 58586 974977 994693 2066102
n: 30006 51596 815477 795344 1692423
r: 26958 53239 801514 774606 1656317
g: 23689 57734 666533 790131 1538087
d: 23304 36637 746244 697523 1503708
:: 15442 27059 639115 649013 1330629
w: 25563 41061 622672 629215 1318511
1: 9697 12580 577523 561429 1161229
l: 21855 32824 560110 542960 1157749
2: 9890 13516 492565 514385 1030356
u: 11878 15246 440808 431176 899108
0: 10333 13106 404229 445998 873666
v: 7450 8415 328991 292590 637446
b: 9980 26743 280533 285767 603023
3: 6296 6905 299391 272352 584944
f: 9866 25830 265685 266037 567418
4: 4738 5931 273161 244104 527934
k: 4202 5641 235501 230456 475800
5: 5957 6920 212941 235172 460990
7: 6497 7333 230677 200956 445463
9: 4327 5215 206613 195295 411450
8: 5363 6697 210689 178565 401314
6: 5761 6487 209092 175203 396543
x: 3853 5755 168401 144265 322274
-: 3516 11325 124398 133481 272720
y: 4348 5272 114803 96971 221394
_: 2301 2683 87749 80901 173634
j: 4436 5058 89043 72567 171104
=: 1555 1437 37342 35214 75548
q: 1494 1538 32910 37861 73803
z: 741 907 29563 30037 61248
,: 3282 2848 21099 14688 41917
&: 493 413 12558 9222 22686
%: 220 460 9640 11420 21740
;: 2878 2254 8281 8281 21694
?: 322 294 4796 9264 14676
+: 45 35 1333 1758 3171
~: 31 7 996 735 1769
$: 0 0 425 670 1095
^: 6 0 420 228 654
*: 27 10 187 188 412
!: 0 2 282 122 406
[: 0 0 292 23 315
]: 0 0 272 23 295
|: 8 8 77 167 260
@: 10 0 113 38 161
(: 0 0 75 55 130
): 0 0 69 55 124
{: 0 0 75 0 75
\: 0 0 6 4 10
': 0 0 1 1 2

Does it have any practical use?
Perhaps. In proxy.pac files, a common method of load balancing based on URLs, known as the Sharp Superproxy script, is to sum the ASCII values of the cache entries, and mod it by the number of servers, to pick a server to use. .pac files are javascript, and javascript does not have an easy method to return the ascii value for a character. So what's generally used is a function like:

function atoi(charstring) {
    if (charstring=="a") return 0x61; if (charstring=="b") return 0x62;
    if (charstring=="c") return 0x63; if (charstring=="d") return 0x64;

This can be speeded up by ordering the list in the order of frequency, starting with "/", "t", "e", ".", "o", "a" - just moving those few to the front, reduces the latency of the script significantly.

Also, hashing in URL history handling can be sped up if the most prevalent buckets are created. This could also be useful for other URL collections, like AV software URL matching. I am unaware of any that work directly with character based lookups, but it is certainly one way to do it.

Other uses?
In pen testing, having a frequency table like this can greatly aid in URL discovery speed.

But all in all, it was a fun exercise. Note that the variations may be great, especially for the bottom half of the list. Also note that the low count for the letter 'x' in the URLs might not match your users.


Slashdot clandestinely scanning its users

arth1 arth1 writes  |  more than 5 years ago

I just discovered something I'm not sure I like.

Whenever I post something to slashdot, slashdot connects back to port 80 on the machine I post from, looking for an open proxy on port 80.
This isn't behavior I really like to see. It's unsolicited, and more to the point, it takes advantage of a local firewall possibly being temporarily open for traffic FROM an address for a short while after connecting TO it.
There might be a "good cause", like collecting a list of open proxies for the poor guy behind the Great Firewall of China or something similar, but it's still unsolicted, clandestine and not documented.

Here are a couple of web log entries showing this: - - [10/Sep/2008:15:47:47 -0400] "GET HTTP/1.0" 404 271 "-" "libwww-perl/5.812" - - [10/Sep/2008:20:32:18 -0400] "GET HTTP/1.0" 404 273 "-" "libwww-perl/5.812"

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