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danarmak commented on Async hazard: MMAP is blocking IO   huonw.github.io/blog/2024... · Posted by u/mmastrac
nemetroid · a year ago
So what is the definition of "blocking" here? That it takes more than 1 µs?
danarmak · a year ago
That the process/thread enters kernel mode and then is suspended waiting for IO or for some other event. As long as the thread is running your code (or, is scheduleable) it's not blocked. And then the async implementation can ensure your code cooperatively gives up the CPU for other code.
danarmak commented on Async hazard: MMAP is blocking IO   huonw.github.io/blog/2024... · Posted by u/mmastrac
magicalhippo · a year ago
It still blocks. It just completes orders of magnitudes faster.
danarmak · a year ago
No, if the memory-mapped page you're accessing is in RAM, then you're just reading the RAM; there is no page fault and no syscall and nothing blocks.

You could say that any non-register memory access "blocks" but I feel that's needlessly confusing. Normal async code doesn't "block" in any relevant sense when it accesses the heap.

danarmak commented on I tested four NVMe SSDs from four vendors – half lose FLUSH'd data on power loss (2022)   twitter.com/xenadu02/stat... · Posted by u/whitepoplar
worthless-trash · 2 years ago
I do not know how zfs will overcome hardware lying. If its going to fetch data that is in the drives cache, how will it overcome the persistence problem ?
danarmak · 2 years ago
It will at the very least notice that the read data does not match the stored checksum and not return the garbage data to the application. In redundant (raidz) setups it will then read the data from another disk, and update the faulty disk. In a non-redundant setup (or if enough disks are corrupted) it will signal an IO error.

An error is preferred to silently returning garbage data!

danarmak commented on Mozilla's midlife crisis has taken it from pioneer to Google's weird neighbor   theregister.com/2023/09/2... · Posted by u/mrzool
nfriedly · 2 years ago
I'm mostly a Firefox on Android user, does Chrome on Android have plugins now? I know it didn't for a while.
danarmak · 2 years ago
I assume you mean extensions, not plugins. No, Chrome doesn't support extensions on android, but some Chromium reskins do.

That said, the most important extension usecase is adblocking, and with Manifest v4 and FLoC/Topics and SafetyNet/remote attestation, well...

danarmak commented on When root on ZFS breaks on Arch Linux   blog.mnus.de/2023/03/arch... · Posted by u/LinuxBender
denotational · 2 years ago
> ignore these and accept a tainted kernel

That isn’t possible as I understand it.

Loading any non-GPL module will mark the Kernel as tainted, but that’s not the issue here.

The problem is that the ZFS module uses Kernel symbols that are marked as GPL-only, meaning that the Kernel will refuse to load the ZFS module as it isn’t marked as a GPL module. There isn’t any way to bypass this short of recompiling the Kernel to remove this restriction.

The legal status of this is uncertain, since a number of questions naturally arise:

1. Is it acceptable to mark a Kernel module as a GPL module (this is done via a macro in the source) but release it under a license that is not GPL-compatible?

2. Is it acceptable to recompile the Kernel to remove this restriction?

As far as I know neither of these have ever been tested, and there are differing opinions.

danarmak · 2 years ago
If a kernel with the restriction removed is compiled locally and is never redistributed, why would it be illegal?
danarmak commented on Lastpass Security Incident   blog.lastpass.com/2022/11... · Posted by u/bartkappenburg
danuker · 3 years ago
I feel your pain. I switched to KeePassXC, and will never use an online password manager again.

For a password management company, they can't even be bothered to fuzz their export functionality. QuickCheck works unreasonably well on `import(export(a)) == a`.

But maybe it's intended to be buggy, in order to keep you in their walled garden. Clearly the sync between devices works, so they have solved this problem.

danarmak · 3 years ago
> Clearly the sync between devices works, so they have solved this problem.

Presumably they don't use CSV to sync, they're using a saner json/etc. data structure that they're not letting us export ourselves. Seriously, being limited to CSV in this day and age...

danarmak commented on Homeland security reaches the anus (2007)   thelancet.com/journals/la... · Posted by u/daenney
danarmak · 3 years ago
Should say, [2007]
danarmak commented on Employers’ Use of AI Tools Can Violate the Americans with Disabilities Act   justice.gov/opa/pr/justic... · Posted by u/pseudolus
marian_ivanco · 3 years ago
I am not sure, but if I remember correctly employer must prove they are not discriminating. And just because they are using AI they are not immune to litigation.
danarmak · 3 years ago
How can the employer prove a negative?

At most I imagine the plaintiff is allowed to do discovery, and then has to prove positive discrimination based on that.

danarmak commented on Scientists have found a way to harden wood to make a knife that rivals steel   cbc.ca/radio/quirks/oct-2... · Posted by u/curmudgeon22
agumonkey · 4 years ago
Just reminds me that paper moved fast enough can probably already cut meat
danarmak · 4 years ago
I got a papercut and I'm made out of meat!
danarmak commented on The Insecurity Industry   edwardsnowden.substack.co... · Posted by u/stanislavb
aj3 · 4 years ago
Your second link mentions sellers avoiding liability by selling product (that can be inspected in stores) "as-is". It could be argued that open source falls in the same category. You have an opportunity to inspect it before using and if you don't like it or don't feel qualified to pass judgement, no one is forcing you to use it.
danarmak · 4 years ago
The second link doesn't mention "as-is", the first one does. I'll assume that's what you meant. It says,

> Though manufacturers cannot so easily escape liability, sellers can escape liability by informing the customer before the purchase that a product must be taken "as-is,” which means how the product was found when it was purchased in-store. “As-is” works because the buyer has an opportunity to inspect the product and decide whether to buy it given its condition.

On that analogy, Github and RedHat aren't liable, but the original author of the software still is.

u/danarmak

KarmaCake day1098August 8, 2015View Original