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Comment by tomxor | Hacker News Reader

> And I learnt that even when it is not used (not sure it the lid was closed) a macbook can cause significant interference to the wifi for all other nearby devices.

My partner has an older MBP, I noticed this the last time she was forced to updated her OS a major version... the thing no longer sleeps when you tell it to or when you close the lid, it will stay connected to wifi and quite happily saturate the network downloading updates.

Only way to be sure is to power off the stupid thing.

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My understanding is this is an issue with new features of all sorts of laptop/desktop devices.

For example, https://news.ycombinator.com/item?id=28639952

"Do not leave XPS laptop in any sleep/hibernate/standby mode when placed in a bag" because they stay connected to wifi and may attempt to run updates etc when the user is not expecting or prepared for that, as far as cooling.

I own an XPS, it runs Debian, it only installs updates when I tell it to.

Even if I decided to use the untended upgrades package, it wouldn't do it when I sleep the computer... that would just be stupid.

Yeah it might be unwanted behavior for your particular setup. Personally, on macOS and windows, I would prefer not to be at the computer when an update occurs - I also dont want to have to go do something else while I wait for the update. Just feels like a waste of time in my opinion. However, if I had reason to care about an update or the changes it was introducing I too would not want background updates running when I put my machine to sleep. I guess for an average user updating when the machine is not in use is a feature, while for the tech crowd that kind of behavior can mess with your preferred setup.

I always assumed it was smart enough though not to do it when it's on battery as it is very likely that the device is also in a confined space, such as a laptop backpack waiting for the trip to the office next morning.

If I have it sitting on power and thus likely just on the top of the table and I have auto-updates on, sure do them when I'm not around as long as they are updates that can run unattended. Note the "if auto-updates are on" part, which luckily you can still disable on MacOS.

I think macOS has a minimum battery charge requirement that has to be met before an update occurs in the unplugged scenario.

people on linux wait for updates? i thought that was a thing only for mac and windows... never noticed or seen a update screen on linux unlike the Windows nightmare where it would even kick you out of your work to do a damn update

Don’t know what people on Linux do, I only referenced macOS and windows.

people on linux wait for updates?

Yes, Fedora downloads packages first and then reboots the machine to perform the actual updates and then reboots again into the updated system [1]. You can still run dnf update manually, but the recommended path is the former one. Why? Because in contrast to what many commenters say here, in-place updates of Linux systems can go wrong. Apparently, Fedora have encountered this often enough that they they have started doing 'offline updates'.

(The proper solution, which Silverblue/Fedora IoT/Fedora coreOS/NixOS/GUIX do is to make system updates atomic with roll-back.)

[1] https://fedoramagazine.org/offline-updates-and-fedora-35/

just checked how Fedora does it... it just downloads the updates and when you shutdown it installs them for you before it finally shuts down, doesn't seem as bad and not how you said it was.

You are wrong. See the specification on the Fedora Wiki:

https://fedoraproject.org/wiki/Features/OfflineSystemUpdates

The system update mode is implemented by booting into a special target. The target installs the downloaded updates and then reboots back into the regular default target.

You can also see the process in the video on the end of this page:

https://www.addictivetips.com/ubuntu-linux-tips/upgrade-fedo...

You can see that after choosing to install the updates, the system reboots. Then it uses systemd functionality to switch into a special update target. Then it reboots again to boot into the updated system.

Finally, also see the article that I linked in the earlier post:

https://fedoramagazine.org/offline-updates-and-fedora-35/

The process of restarting, applying updates, and then restarting again is called Offline Updates. Your computer boots into a special save-mode, where all other systems are disabled and where network access is unavailable. It then applies the updates and restarts.

I am currently using Fedora headless. But the last time I used Fedora on the desktop (~a year ago), I am pretty sure it still did the reboot-update-reboot dance. The exception to this is Fedora Silverblue, which downloads a new system image and then boots into that in a single boot.

Running updates are only a problem on Mac or Windows. Updates on the different linux flavors I’ve used take fractions of the time, are unobtrusive (I can continue to do work), and as a bonus, never fail to make my aging self feel like a technoir hacker with all that rapidly scrolling text. It’s all whole different ball game.

Different user groups, different priorities. I had a colleague who was a seasoned C hacker and long-time Linux user (but not someone who'd be very interested in how a Linux distribution or package manager works). Their Ubuntu system indicated that there were updates. So, they started the update. However, it was taking too much time and they wanted to go home, so they shut down the machine during the update. Unfortunately, it left the system in a bad, (IIRC) unbootable state and the local sysadmin had to spend an hour to get the system in a consistent state again.

Is it reasonable to expect that you can just yank the chord during an upgrade? Maybe, maybe not. But users have the expectation that it is ok, there can be a power interruption after all.

This would never happen with a macOS update, which uses an immutable root file system and APFS containers to switch the root after an update. Or an OSTree system like Silverblue, Fedora IOT, or Fedore CoreOS. Traditional Linux packages fall flat on their face in such scenarios (unless you use a lot of band-aid like filesystem snapshots, set up GRUB to handle boot into the right snapshot, etc.)

I think it is uncharitable to assume that the people making macOS (or Windows) update are incompetent. They may just have a different set of requirements and constraints.

That’s a good story. I thought apt can usually recover from incomplete updates, but maybe it was in the middle of a kernel or bootloader update or something when power got killed.

> This would never happen with a macOS update, which uses an immutable root file system and APFS containers to switch the root after an update.

There are still things that cannot be interrupted like flashing firmware blobs, on many devices. Before apple distributed updates using FS snapshots they would reboot the machine first and block the user with a message that it cannot be interrupted.

It's also not a completely free or well implemented solution because (even as an x-apple user) I am made patently aware of just how absurdly huge their updates are, even for the smallest patch... incremental distribution and immutable FS based updates are not fundamentally incompatible, so I guess Apple simply doesn't respect user's bandwidth or assumes all of their customers have gigabit downlinks for the exclusive use of Apple devices.

> This would never happen with a macOS update, which uses an immutable root file system and APFS containers to switch the root after an update.

Hehe, oh yes you can still have data loss on macOS. See the recent article about how macOS SSDs use write-cache enabled.

Sure you can have data loss. But we were talking about updates. Most image-based systems do not update in-place, but write the updated system first and flip the switch atomically when the update is successful. macOS 11 and later cryptographically verify the new on-disk system volume and boot into the old system if the verification fails:

https://support.apple.com/en-au/guide/security/secd698747c9/...

SSV not only helps prevent tampering with any Apple software that’s part of the operating system, it also makes macOS software update more reliable and much safer. And because SSV uses APFS (Apple File System) snapshots, if an update can’t be performed, the old system version can be restored without re-installation.

Or do. Then get refund when it cooks itself and buy a computer you own.

Dunno if the new MacBook Pro M1 Pro / Max are more thermally efficient or that they don't start back up in a bag but I've left mine in sleep in a sealed bag and it wasn't warm to the touch at all.

Did you have auto-update on?

Yes

There probably were just no updates available at the time.

Considering I’m on the beta channel because I have dev account I don’t think that’s true.

I have had this issue with Thinkpads as well. The solution was to make sure to unplug the AC power adapter before putting it to sleep and putting it in my bag. Else it would go to sleep thinking that it's still on AC power, and happily wake itself up to install updates while in my bag. If power was disconnected after putting it to sleep, it would not be able to know it was on battery power.

Yesterday my home DNS weren't resolving and noticed on PiHole that there were >30,000 requests of *.in-addr.arpa (Reverse DNS Lookup) from the iPhone+iPad of the guest to whom I gave the WiFi access and was saturating the Pi's CPU. I re-enabled rate limiting on PiHole and blocked the request with a filter.

A cursory search on the issue says Bonjour is the culprit, I'm forwarding DNS requests to my PiHole instances on my gateway and latest iOS doesn't seem to like it; I haven't faced such issue earlier and I have this setup for several years now.

https://support.apple.com/guide/mac-help/turn-power-nap-on-o...

Tried it, didn't work, I also dug out the old pmset command but it seems to have been neutered.

I'm glad I stopped using Apple stuff 10 years ago, their macs are gradually devolving into iDevices.

Sleep isn’t any different than it used to be.

“pmset -g assertions” will show you why it thinks it’s awake, it could be a silent video playing in a web browser or something. (and of course, if you can ssh in to run that it must be awake.)

they already mentioned why it was awake: downloading updates.

...which it only does when connected to power so I'm honestly failing to understand what the problem may be. Anyway: Settings -> Software updates -> Advanced -> Download new updates when available -> uncheck.

For everything else: Battery -> Power adaptor -> Wake for network access -> uncheck (may also take care of the above, dunno)

For extra fun, if while it's sleeping it's connected to a Display Port or USB-C display, it'll wake it up everytime it wakes the wifi for its 'power naps'. Disabling them in System Prefs doesn't change this.

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