Async IO Settings for Virtual Disks: Documentation? How to Set?

[SInisterPisces]

Me again, looking for more help with Probably Dumb Questions.

Maybe because I'm new at this I don't know what I should be searching for, but after some googling and searching here, I'm still looking for a good explanation of the Async IO options in the virtual disk options inside a VM.

I've got no idea what this does, so I've been leaving it at default. Are there any articles that explain what the other two options do/when I'd want to use them?

Thanks!

 

[LnxBil]

I've got no idea what this does, so I've been leaving it at default. Are there any articles that explain what the other two options do/when I'd want to use them?

What I found is that the io_uring is the very recently added and fastest method of doing asynchronous IO. I found this FOSDEM presentation (and video) which explains the new method in detail and skimmes the surface on what the others are.

 

[SInisterPisces]

What I found is that the io_uring is the very recently added and fastest method of doing asynchronous IO. I found this FOSDEM presentation (and video) which explains the new method in detail and skimmes the surface on what the others are.

Excellent! I'll check that out soon.

I have to say, I'm really impressed with how the defaults in Proxmox tend to be the best setting. One reason I'm posting so much is that I'm using to having to heavily tweak the defaults whenever I set up anything that has any kind of built-in storage. (OpenMediaVault; QNAP NAS devices, any ARM SBC with an SSD attached...)

 

[LnxBil]

I have to say, I'm really impressed with how the defaults in Proxmox tend to be the best setting. One reason I'm posting so much is that I'm using to having to heavily tweak the defaults whenever I set up anything that has any kind of built-in storage. (OpenMediaVault; QNAP NAS devices, any ARM SBC with an SSD attached...)

Yes, the defaults are very good. I also tried to optimize it myself and thought "i know more", but ran into strange problems and unpredictable performance glitches and just went back to the default and they're almost all gone.

Yet, I have to say, that you need to look at the settings once in a while (e.g. every 2 major relases) in order to check if the once-default setting is still the best setting, but besides that ... it's awesome.

 

[SInisterPisces]

Yet, I have to say, that you need to look at the settings once in a while (e.g. every 2 major relases) in order to check if the once-default setting is still the best setting, but besides that ... it's awesome.

I'm going through LearnLinux.TV's YouTube video tutorial series for n00bs right now, and I very much recommend it. It's taking me longer, though, because I'm stopping to make sure I understand what all the options he's not using do.

I'm taking notes, too, for purposes of being able to recreate my setup in the event of catastrophe, so hopefully even if there are major changes in the future it won't take me so long to get caught up as it's taking me now.

 

[Catwoolfii]

I'll just leave it here
https://security.googleblog.com/2023/06/learnings-from-kctf-vrps-42-linux.html
https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/4228112