Reinstall the os and forgot to install zram and I paid for it

What is zram?

Swap but better it behave mostly like actual ram and fast too, not as fast as actual ram but still way faster than swap I can open 5 browser tabs one of them playing a video while compiling a software I don't feel my system slow down at all

It's a Linux feature to compress some of your memory and then store it in a RAM disk. For systems with limited memory, it makes it go further.

https://en.wikipedia.org/wiki/Zram

zram, formerly called compcache, is a Linux kernel module for creating a compressed block device in RAM, i.e. a RAM disk with on-the-fly disk compression. The block device created with zram can then be used for swap or as a general-purpose RAM disk. The two most common uses for zram are for the storage of temporary files (/tmp) and as a swap device.

Look at Mr. Fancy pants over here with 11 cores.

I'm just jealous

1. It starts with 0.

12, because they're zero-indexed.

Probably six cores with hypethreading or the AMD equivalent.

I wish, it's a Ryzen 9 5900hx with only 8cores what you seeing is threads which I have 16 of them

I have a mini PC that has been barreling through NVMe disks but Alpine Linux’ “usb” install mode just wasn’t great either. So I use a “sys” install mode (traditional) on an NVMe disk but have directories like /var/log, /tmp, etc. mounted as zram disks with Zstandard compression. It’s been pretty fantastic honestly.

AMD’s version is called Simultaneous Multithreading (SMT). But just about everyone, even most motherboard firmware that I have seen, calls it hyperthreading still.

sneers in 48GB

I upgraded to 64GB RAM a year or so ago which I didn't really need, but it was cheap so why not.

How things have changed.

Edit: No swop? 🫪

Like with a slowly rolling unbraked car: Don't take photos if you can prevent the crash

It didn't suck enough already buying PC parts in Australia?

I always confuse ZRAM and ZSwap. From my understanding ZRAM is the better one and Zswap is kinda outmoded.

It turns into a rabbit hole every time I gotta reference it! Lol

Now it's starting to look like upgrades are just a thing of the past and this is going to be my forever machine.

I hope you're wrong.

Swap is overrated (/s)

Is it just me or building with

cmake --build --parallel

Crashes with out of memory every time?
Maybe it depends on the project but idk

Did the same, even if it's "just" DDR4 i still feel like RAM nobility nowadays.

I hope I am too, but I just looked at what a CPU, motherboard and RAM upgrade would cost and it looks like this system will be old enough to start high school by the time I replace it.

And the system after that? If I buy new in 2030, when will the one after that be? 2045?

From my understanding, it's the opposite. Zswap is the better one since it has a ZRAM-like compressed section of RAM and disk-backed swap. That's definitely an oversimplification though.

I agree it's confusing. I always look it up during setup so I know which one to use.

Some people think that. I tried it to see what would happen, I have enough that I never threatened to hit the ceiling during normal use so it was uneventful. I turned swap back on and forgot about it for a couple weeks, when I checked about 12GB of swap was in use. So even if you have plenty of ram don't discount swap, it's still going to help.

Which is sad. SMT is the tech, HT is the marketing from intel.

I bought 256 GB of DDR3 for my HP DL380p 3 or so years ago? It was $330 Canadian at the time...

There is a lengthy thread on Reddit about the technical differences. Apparently Zswap will take advantage of the kernel eviction strategy for swap space. Apparently Zram doesn't have that. To me that never made sense because, you create a Zram block device and then set that as your storage for swap space. Why would the kernel care, or know, that the swap space is backed by a Zram block device.

I do use Zram for my cloud self hosting machines and my dev machine. On the cloud devices they have 1 or 2 GB of ram and on my dev machine I have 32GB of ram. And in both cases it definitely seems like there is swap eviction. I also set the vm.swappiness to 180. Prior to Zram I would set my machines' swappiness to 10. Swapping is highly encouraged on my machine.

I think things are going to change. Apple is talking about buying ram from Chinese ram companies. If that happens, a lot of other companies will do the same and that should reduce pressure on ram quite a bit. I'm sure those long term contracts the AI companies have for expensive ass ram will get canceled quick.

Still get that issue with swap and whatever zthing I use

It's the opposite actually, in terms of implementation Zram is a hack, but it does have it's use case when your system load doesn't far exceed your total RAM, on the other hand swap is tightly integrated into the system and it's on it's way to implement "Virtual Swap" which is effectively Zram but not a hack, making it like a hundred times better, see This blogpost for a detailed explanation

Dummy question… if you have an ssd, why not swap?
Sure not the best but also that is the last resort and on ssd Is not as bad as it used to be on hdd

Hah, sympathies. I had a similar scrot-before-disaster recently... oh yup, there it is https://lemmy.wtf/post/44743724/23091152 ... those pebkac errors still sneak up on us. n_n

yeah, until...

I had a fellow linux user friend of over a decade convince me to try go no swap for a change.

I pebkac'd the system before it got a chance to fall foul of having zero swap.

... My next computer even before that pebkac, has swung the other way... >3X RAM amount of swap (And that's on twice the RAM too. Mmm. Roomy.). Not going back to no swap. I prefer the headroom.

With fast drives snug on the mainboard, it doesn't hurt dipping into swap.

Have you tried downloading more RAM?

Why not just set kernel swappiness to 1 and not do any of that?

Yea, I'm wondering if people don't realize the kernel has a swappiness setting. You can turn it down to lower the priority given to swap.

Because I want to encourage more swapping, not less.

But.. Why? If ZRam uses RAM as compressed swap, what advantage does it have over just leaving that RAM available as shared memory? Do you have a specific process that is eating up non-shared? This might be of interest: https://chrisdown.name/2026/03/24/zswap-vs-zram-when-to-use-what.html

You get more ram for very little slow down, that also, would rarely be the bottleneck. For the servers, ram is a constraint, and it's all just selfhosting. I have a Raspberry Pi that I selfhost with, as well as a couple 10 dollar compute instances in the cloud. More ram is much better than the tiny slow down that might occur during compression or decompression. All my services are all still very snappy, even the mailserver. For my work, I bring up large docker sandboxes of services that I need running to test entire systems. In the past, I would just allocate 32GB to a swapfile. ZRam is way faster.

But you also get that with shared memory in zswap, with all the other advantages. I'd really recommend reading the "Architectural differences" in the linked article from Chris Down, as he's way deeper into the kernel code than me, but the biggest problem in a setup like a small memory server is:

• If you have a ZRAM device, and it fills up, more recently needed pages end up on the backup disk swap, because ZRAM has no way to move between swaps

• Where zswap is built into the kernel memory management layer, so it can automatically decide which pages are cold and put them on disk, while keeping fresh ones in compressed RAM.

I.E. in your use case, zswap is better, not even taking into account all the other details from Chris' article.

I looked at the article, same as the reddit thread, probably written by the same person. ZSWAP is just not necessary. ZRAM works and doesn't require disk space w/ 3:1 compression. If I was running out of swap, then yes, I would take a look at ZSWAP to improve my swap situation. It's just not a thing with ZRAM, not for many years.

I.E. for my use cases, ZSWAP is irrelevant.