TPA-RFC-55: Swap file policy

added Next label

I've marked TPA-RFC-55 as proposed.

added Needs Review label and removed Next label

Since we've only just recently returned from CR I'll give this an extra few days just to make sure everyone gets the chance to chime in.

i think the only remaining question i have about this proposal are:

what will happen to existing machines? nothing? so this means we'll basically have swap partitions around indefinitely?
when will we do the actually (and rather complicated) work to fix all our installers?

what will happen to existing machines? nothing? so this means we'll basically have swap partitions around indefinitely?

I guess nothing for now. Switching to swap files could be a lot of (sensitive) work because it would involve messing with storage configuration in ganeti and /etc/fstab. Maybe that's something we could include as part of the upgrade to bookworm?

when will we do the actually (and rather complicated) work to fix all our installers?

A ticket would need to be created once the RFC is adopted. For the ganeti instance installer, the one we use most often, I don't think much needs to be done since a swap file is already created when a swap partition is absent. We might have to look into adjusting the size though, since its 512MB IIRC.

It would be great to have both of those ideas in the proposal so we know how to move forward once the proposal is adopted.

For existing machines, in particular, I am not sure I would go through the trouble of converting everything.

What's the harm in keeping existing partitions?

What was the original idea with your proposal? Convert new installs or everything?

Thanks!

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On 2023-05-23 13:42:19, Jérôme Charaoui (@lavamind) wrote:

Jérôme Charaoui commented on a discussion: #41115 (comment 2905104)

what will happen to existing machines? nothing? so this means we'll basically have swap partitions around indefinitely?

I guess nothing for now. Switching to swap files could be a lot of (sensitive) work because it would involve messing with storage configuration in ganeti and /etc/fstab. Maybe that's something we could include as part of the upgrade to bookworm?

when will we do the actually (and rather complicated) work to fix all our installers?

A ticket would need to be created once the RFC is adopted. For the ganeti instance installer, the one we use most often, I don't think much needs to be done since a swap file is already created when a swap partition is absent. We might have to look into adjusting the size though, since its 512MB IIRC.

-- Antoine Beaupré torproject.org system administration

If you look at the RFC, under Scope, I put:

All new systems including virtual and physical machines. Currently deployed systems are considered out of scope for this proposal.

So in my view, I don't think we really need to determine here and now, if we'll convert existing machines or not to swap files.

I think for some machines, depending on the configuration, (eg. one with very large swap partitions) it might eventually make sense to convert it to swap file. If we adopt this proposal saying we won't convert any machines, then we'll have an annoying contradiction to deal with.

Also, by new systems I mean it in the sense of "going forward", not "new" as in "recently installed".

And when I wrote it is proposed to adjust our machine creation policies and tools to use file-backed swap instead of swap partitions it was kind of self-evident to me that this implies "tickets will be created" but I can spell it out in the text if you think it's needed.

Yeah, I think all of this should be made explicit:

how will we proceed going forward?
what will be converted, and when?
bring existing machine in scope and describe what will happen to them ("unsure, depends" is okay!)