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24-core CPU and I can’t type an email

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Re: 24-core CPU and I can’t type an email

#301

Post by [deleted] »

brucedawson wrote: post #31
bonestamp2 wrote: post #27

Side note... not related to the same root cause, but related to a similar end user problem... I've been staying in a lot of hotels lately and using a lot of very slow internet connections (not by choice, that's just what is available) and I wish Chrome had some sort of "low bandwidth" mode where it would only allow requests from your current tab, or maybe current window (easily open a new window to control which tabs…

Not a bad idea. Feel free to file a bug/suggestion at crbug.com, and I'll try to suggest such a tweak myself. We already do throttle hidden tabs, but I don't think we throttle their bandwidth usage directly. It is tricky, unfortunately.

[deleted]

Re: 24-core CPU and I can’t type an email

#302

Post by bonestamp2 »

saltcured wrote: post #55
bonestamp2 wrote: post #27

Side note... not related to the same root cause, but related to a similar end user problem... I've been staying in a lot of hotels lately and using a lot of very slow internet connections (not by choice, that's just what is available) and I wish Chrome had some sort of "low bandwidth" mode where it would only allow requests from your current tab, or maybe current window (easily open a new window to control which tabs…

Ironically, I think people on slow connections were early pioneers of using tabs for asynchronous/background page loading. I don't remember where I learned the technique first, but when I was roaming the world and getting work done via GPRS internet, I'd open links in a new tab and let them slowly load in the background. I'd view the tab later and see the fully rendered content. It would absolutely kill this use case…

Yes, that's funny. I guess for me it's when I open my browser to do something quickly, but can't do it quickly because I have to wait for all those tabs to load first.

Re: 24-core CPU and I can’t type an email

#303

Post by CodeWriter23 »

speedplane wrote: post #299
CodeWriter23 wrote: post #277

Earlier quoted context omitted.

In the article, they illustrate a poor design choice. Or probably more likely, a continuation of the programming practice utilized elsewhere in the kernel. That being, slap a lock on any resource contention. That practice is necessitated solely by the need to support a linear calling interface. Even if this particular issue were to be fixed through queuing instead of locking, the existence of locks elsewhere will sti…

Don’t see the fundamental difference between locks and queues. In a system that uses locks, the kernel can still internally use queues to grant some lock requests before others.

The fundamental difference is this. With locking, when a thread’s time slice expires while holding a lock, the dispatcher switches to a different thread and no other thread can gain that particular lock until the dispatcher resumes the thread holding the lock.

No locks means this can never happen.

Re: 24-core CPU and I can’t type an email

#304

Post by polkadotted »

AnIdiotOnTheNet wrote: post #243
polkadotted wrote: post #235

Earlier quoted context omitted.

This is a blatant lie that needs to stop. I've been using linux exclusively on laptops for more than 10 years. The first 5 with the HP EliteBook like, currently with Lenovo X1 line. On my current X1 Yoga 1st gen, I do regularly get almost 1.5x the uptime on battery compared to windows 10. We got a batch of X1 Carbon 6th gen, which are "optimized for windows 10", where the S3 sleep state was replaced by the S0I3, whic…

Today on Linux Evangelism 101: using a single anecdotal experience as proof that something works right always.

Sure, however I really like to see what downvoters have to say. The "power management is bad" is pretty generic, isn't it?

High-end laptop lines (Dell, HP, Lenovo) have actually pretty good linux support, they are almost always intel i5+ cpus with integrated graphics which are all very similar. There is next to zero setup required in almost any case. This is known. The drivers are tried and tested. I've never experienced any random "power management issue". Suspend/resume/battery consumption/acpi is working perfectly fine. What else does qualify for "power managment"??

I've been supporting a team of 20+ people with these lines in a mixed environment, and linux since more than a decade was always basically plug and play.

There have been some quirks in some models, which generally required some tweaks in the kernel boot line, to fix issues with backlight tweaking.

Re: 24-core CPU and I can’t type an email

#305

Post by polkadotted »

rocho wrote: post #261
polkadotted wrote: post #235

Earlier quoted context omitted.

This is a blatant lie that needs to stop. I've been using linux exclusively on laptops for more than 10 years. The first 5 with the HP EliteBook like, currently with Lenovo X1 line. On my current X1 Yoga 1st gen, I do regularly get almost 1.5x the uptime on battery compared to windows 10. We got a batch of X1 Carbon 6th gen, which are "optimized for windows 10", where the S3 sleep state was replaced by the S0I3, whic…

I get 6-8 hours out of my Zenbook with ArchLinux. Nowhere near the touted 9 hours of the specs, or the 12+ of the Macbook. My system is exceptionally lean. I run bspwm and the radios are always off except WiFi. Still, I feel like I could get a lot more from this laptop. I cannot (and I certainly wouldn't want to) install Windows on dual boot to make a comparison though. What distribution do you use?

How can you compare two different laptops? I'm comparing windows and linux on the same laptop.

I personally use debian unstable with a tiling window manager (awesomewm) without a specific DE. However, I generally setup Mint for all my colleagues on the same laptop lines, and there's one colleague running Arch. We all have very similar battery lifetimes.

Re: 24-core CPU and I can’t type an email

#306

Post by mwcampbell »

polkadotted wrote: post #304
AnIdiotOnTheNet wrote: post #243

Earlier quoted context omitted.

Today on Linux Evangelism 101: using a single anecdotal experience as proof that something works right always.

Sure, however I really like to see what downvoters have to say. The "power management is bad" is pretty generic, isn't it? High-end laptop lines (Dell, HP, Lenovo) have actually pretty good linux support, they are almost always intel i5+ cpus with integrated graphics which are all very similar. There is next to zero setup required in almost any case. This is known. The drivers are tried and tested. I've never experie…

> High-end laptop lines

Sure, but Linux really ought to shine on the low-end laptops.

Re: 24-core CPU and I can’t type an email

#307

Post by oso2k »

speedplane wrote: post #297
oso2k wrote: post #279

Earlier quoted context omitted.

This has nothing to do with Moore's Law or improving processors directly. If anything, this is a software optimization problem. Half of what I mentioned was locks and schedulers, which are directly software problems. Layer on the fact that a helloworld application in most languages and frameworks is 100s of KB to dozens of MBs, and you have really, really, unoptimized software. 30 years ago, lots of software was writ…

> This has nothing to do with Moore's Law or improving processors directly. If anything, this is a software optimization problem. This is such a contradictory sentence. The whole point of Moore's law was that software developers could do what they want, freed by limitations of hardware because in 18 months, when their product was ready for launch, the hardware became capable enough to handle it. Forcing developers to…

You don't understand Moore's Law. Moore's Law says nothing about software devs doing what they want or processor speed or even hardware capabilities or qualities. It's about the manufacturing capability and integration by semiconductor fabs. Specifically, "Moore's law is the observation that the number of transistors in a dense integrated circuit doubles about every two years.' [0]. Hardware engineers never gave up; they're the reason your bloated apps takes 60 secs to startup instead of 3600 secs.

[0] https://en.wikipedia.org/wiki/Moore%27s_law

Re: 24-core CPU and I can’t type an email

#308

Post by CodeWriter23 »

speedplane wrote: post #298
CodeWriter23 wrote: post #143

Earlier quoted context omitted.

If we had an operating system where every system call used an async calling interface, the type of spinlock latency observed in this article would be greatly reduced. It wouldn’t bring Moore’s Law back but it would make the most of what CPU resource we have.

If every OS required async calls, it would require every developer to learn async programming. They probably wouldn't learn it properly, and you'd end up with more race conditions and bugs than if async was optional.

Closures/blocks really make it a lot easier to follow the flow of async coding.

Async style enforces a kind of minimalism that in my opinion simplifies the problem space overall. Obviously, one has to learn different approaches to problem definition and solution to embrace event-driven coding.

To me, in the comparison of linear programming handling an exception when your call stack is 5 levels deep (or maybe 3 in a different use case), having to bubble the appropriate handling at each of those levels, versus async where in your closure you have a 4-line if/else construct that fires off one event for success and a different event for failure, async wins the simplicity competition every time.

If race conditions are an issue, events should be dispatched through a single-threaded finite state machine dispatcher for resolution. Such events can fire up multiple worker threads to do their bidding, but when state changes, that goes through the dispatcher which inherently resolves all races.

Re: 24-core CPU and I can’t type an email

#309

Post by polkadotted »

mwcampbell wrote: post #306
polkadotted wrote: post #304

Earlier quoted context omitted.

Sure, however I really like to see what downvoters have to say. The "power management is bad" is pretty generic, isn't it? High-end laptop lines (Dell, HP, Lenovo) have actually pretty good linux support, they are almost always intel i5+ cpus with integrated graphics which are all very similar. There is next to zero setup required in almost any case. This is known. The drivers are tried and tested. I've never experie…

> High-end laptop lines Sure, but Linux really ought to shine on the low-end laptops.

Linux shines also on low-end laptops as long as you're still decent hardware. Nowdays it's still generally an intel core with integrated graphics, memory and I/O controller, so the result will be pretty much the same. Old, good laptops work even better than brand new editions of current laptop lines.

But this doesn't save you from crappy hardware, which is why this kind of argument is a non-starter for me. How well does current windows editions work on low-end crappy laptops that sell for the lowest tier? Not great. These laptops have plenty of little issues on windows as well.

Maybe better than linux, because the drivers have way more work-arounds than linux has.

Have you ever seen the internal linux quirks table to work around buggy and downright horrid hardware? That's what you get with those. If it works at all is thanks to the patience of people that put in the time to work those issues around. I frankly do not blame linux if it doesn't work well with such hardware.

Re: 24-core CPU and I can’t type an email

#310

Post by polkadotted »

drewg123 wrote: post #252
polkadotted wrote: post #235

Earlier quoted context omitted.

This is a blatant lie that needs to stop. I've been using linux exclusively on laptops for more than 10 years. The first 5 with the HP EliteBook like, currently with Lenovo X1 line. On my current X1 Yoga 1st gen, I do regularly get almost 1.5x the uptime on battery compared to windows 10. We got a batch of X1 Carbon 6th gen, which are "optimized for windows 10", where the S3 sleep state was replaced by the S0I3, whic…

My wife just got the Carbon 6th gen. There is an ACPI patch to restore S3. See https://delta-xi.net/#056 . Once you've got the patched dsdt.aml, I highly recommend not following their directions, and just loading the file in grub by creating /boot/grub/custom.cfg with the line: acpi patched_dsdt.aml This has the advantage of not requiring any manual intervention every time your kernel is updated. The downside is that…

I already did it, and I'm really glad I can do that since I have no use for S0I3 and I'd rather have the extended battery lifetime. However on windows there's no way to disable this sleep mode, and the laptop has consequently lasts way less when put to sleep in Windows 10, even compared to the 3rd edition (which we also have so that I can compare). How does this put linux in power management, huh?

Sadly, the 6th edition of the Carbon also runs waaay hotter than the 3rd, and I did notice occasional coil whine which was previously absent. When running normally the kernel writes regularly about thermal warnings. It seems that power and heat management is not well managed in this edition, and I see similar reports for the x1 yoga 3rd gen.

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