is there any hope for a decentralised cryptocurrency that's scalable?

is there any theorem that proves that this is impossible?

i think cryptocurrency is essentially: cryptographically proving that a chunk of data came out of 'genesis block', and a way to detect double spending.

selsta, so im thinking my issues are because systemd can't handle LMDBs memory magic

<o​frnxmr:monero.social> It works without systemd? (Doesnt sound right)

gingeropolous: does it happen on master or release nodes too?

Custom systemd script?

tesing now on release 18.3.1. It takes a day or so to get up to 40GB.

what's happening? I can't find the beginning of that convo. systemd complains at 40GB?

you can force monerod to cycle thru a lot of RAM, just try to refresh a wallet from block 1

<o​rion_midast:matrix.org> Hey is there any chance we can try to get on Tangem hardware wallet? Its fully open source

<o​frnxmr:monero.social> It uses 40gb of ram? (Cant we limit the sync so it doesnt download so far ahead?)

<o​frnxmr:monero.social> Ask them

ofrnxmr: it doesn't need 40GB of RAM. it uses as much as is free.

<o​rion_midast:matrix.org> I did in their discord sever. They said they added it to the list but thats some retard stuff.

<o​rion_midast:matrix.org> do we have dev power to help them?

<o​rion_midast:matrix.org> or something

<o​frnxmr:monero.social> Hyc - can it be limited with a flag?

<o​frnxmr:monero.social> Something like `block-download-max-size` but for total sync cache?

there is no sync cache

LMDB only uses free RAM. If LMDB is using it, that means nothing else on the system wanted it.

If anything else on the system wants RAM, the RAM LMDB was using will get taken over by the other app, instantly and transparently.

<t​rasherdk:monero.social> I only had a few (100KB -> 1MB) swap activated on a wallet sync. 2 threads, 2 G RAM.

<t​rasherdk:monero.social> Eh, 4 threads and 4 G RAM, 360 M swap.

<t​rasherdk:monero.social> Daemon:

<t​rasherdk:monero.social> ```2023-12-18 15:53:48.272 I Found block <c4bbfb2df77f5467c6cecdcb9e5504e984455ad99448bdf2f5dbaca4ab0807c3> at height 1503370 for difficulty: 219498

<t​rasherdk:monero.social> 2023-12-18 16:00:35.457 I Found block <477b174be12b3c66e6b844a2ec552c9d1882fa4974c758111860775522713e0c> at height 1503371 for difficulty: 218130

<t​rasherdk:monero.social> 2023-12-18 16:13:45.678 I Found block <7f18ef7fbdea0daf137fb98bf92d07e2f4cf77e208a9291d3fdd4484d14a7890> at height 1503378 for difficulty: 217964

<t​rasherdk:monero.social> ```

<t​rasherdk:monero.social> Wallet:

<t​rasherdk:monero.social> ```

<t​rasherdk:monero.social> 2023-12-18 15:51:08.084 W Received money: 2.063935154664, with tx: <1fec7f486687d3f96c15786285295232a0be17adaf43b4aaf9095cdc89b7185e>

<t​rasherdk:monero.social> 2023-12-18 15:53:48.320 W Received money: 2.063778998310, with tx: <dfe0dd9a6bc760b2bb1dc0e438a886f8bf84159a34ce8ddf5a0939003a432d32>

<t​rasherdk:monero.social> 2023-12-18 15:53:48.320 W Received money: 2.063775061964, with tx: <823307248b284b862e7d1a4424af6a5d70248f5e33b858515b2ffe0883cd922e>

<t​rasherdk:monero.social> 2023-12-18 16:00:49.169 W Received money: 2.063771125626, with tx: <c7d19a261b38ef7bce59aa775eaed6dc57f92efc044ec3efbad995beee4c5cf9>

<t​rasherdk:monero.social> 2023-12-18 16:13:50.381 W Received money: 2.068908371466, with tx: <c8718e6cf658163cdb117b42e4c4a28d20f7eed57d7289d648614f783e7521a6>

<t​rasherdk:monero.social> ```

pastebin, dude

<t​rasherdk:monero.social> The short version is, daemon mining and wallet syncing, no more than 50% of 4G RAM is used, and at some point, 360M swap was active.

You should try setting /proc/sys/vm/swappiness = 0. there's no reason for swap to get used if you have free RAM.

a wallet that is up to date won't cause much memory use because it's only going to sync against newly received blocks. it won't cause any more memory to be used than monerod itself would have used anyway.

mining will use 2.3GB

<t​rasherdk:monero.social> `2.73G/3.82G` to be precise 😎

<t​rasherdk:monero.social> The swap usage could be for a number of other reasons. MySQ, Apache and kiddies hitting the firewall.

syncing a wallet from far in the past will force monerod to read older blocks that it wasn't referencing up till then, so RAM use should go up

I just did a rescan_bc soft 1000000 and I can see the RAM use go up on my monerod now ...

from 1000000 to 1851000 added 3.5GB to the process size

rather, to the Shared memory use

<t​rasherdk:monero.social> I'll try to launch a daemon sync and see how that affect memory. I think mainnet is about 2-4K blocks behind on this box.

<t​rasherdk:monero.social> Well, it does snatch up a bit, but not much.

<t​rasherdk:monero.social> matrix.monero.social/_matrix/media/…ero.social/LPrFAXpDkuvfajPsaPgHRxxX

<t​rasherdk:monero.social> matrix.monero.social/_matrix/media/…ero.social/JlFPXZqBfDjfSjGdQWihvldi

<t​rasherdk:monero.social> Does images cross the bridges?

You posted two links to matrix.monero.social before that question. They could be images.

<t​rasherdk:monero.social> So I guess they don't cross.

Well, right now the links do work. But maybe not everybody is in the mood to click :)

<t​rasherdk:monero.social> LOL. Okay. Launching a second daemon added aprox. 2G to memory usage.

<t​rasherdk:monero.social> A few. 20-30M swap.

hyc, the start was here: monero-project/monero #7345

basically, at some point in time (for a reason I forgot), i instructed systemd to do some memory management for monerod

when I pulled in that weak_ptrs PR 7345, i noticed that monerod was being restarted by systemd because it was hitting my 40GB limit

so now im trying to see if release has the same behavior when managed by systemd

sorry for jumping back and forth with communication channels. im never sure which of my musings warrant the permanent record in the githubs

ah. if your box has 64GB RAM then sure, monerod may try to use more than 40GB. is this a public node?

again, if it's only syncing recent blocks, memory use would never get that high on its own

If its the same box as xmrchain, is it possible that its the onion blockchain explorer? People using the api? (Ive a 64gb box that is using between 5-10gb)

yeah, if they're all looking up random stuff, sure

anyway the thing to watch out for is whether the memory use is mostly shared memory or not. if it's mostly shared, that's LMDB and filesystem cache, and nothing to worry about.

if shared is not the majority, then there may be a monerod memory leak.

"If anything else on the system wants RAM, the RAM LMDB was using will get taken over by the other app, instantly and transparently" But what if 2 LMDB instances are running together, like monerod and xmrblocks (the block explorer)?

Right now I have 49.3 GiB for monerod and 7.5 GiB for xmrblocks on p2pool.io

On a 64 GiB system

hm my monerod is only using 1.6GB of RAM and the system has good deal more available

<o​frnxmr:monero.social> Try remote syncing an old wallet (maybe)

sech1: it's all handled by the kernel filesystem cache. Typically some advanced form of LRU cache replacement.