RandomX: print VM allocation warnings only once

[SChernykh]

To reduce warning spam when large pages are unavailable.

[selsta]

I'd prefer if this would get moved to info level log.

On macOS there is no way to remove this warning, we already use VM_FLAGS_SUPERPAGE_SIZE_2MB in RandomX which is the macOS equivalent for huge pages.

[SChernykh]

On macOS there is no way to remove this warning

I googled a bit and it seems you just need to to run with sudo or whatever it's called on macOS. Not a solution for everyone though.

[selsta]

I tried it already with sudo, same warnings.

[SChernykh]

@selsta @jeffro256 I combined both your proposals in the second commit. This should work well for everyone.

[hyc]

Are you sure MacOS hugepages aren't usable? They should still be supported on x86, even though there's no support on aarch64.

[SChernykh]

We do use VM_FLAGS_SUPERPAGE_SIZE_2MB in virtual_memory.c for RandomX, so it should work on MacOS when run with sudo, but @selsta says it doesn't work. I don't have anything from Apple, so I can't check.

[selsta]

I tested on aarch64, will check again with x86.

[hyc]

Yeah, there are docker images to boot MacOS on a regular PC, but they only work with actual Intel CPUs, compatible to the models Apple used. I only have AMD CPUs here.

[plowsof]

can we have this at log level 1 please, this caused me emotional distress because i thought my monerod was secretly mining and when e.g. running blockchain-stats i see the warning in the output:

# DATA
Date	Blocks/day	Blocks	Txs/Day	Txs	Bytes/Day	Bytes
2023-01-17 10:45:35.798	W Couldn't allocate RandomX cache using large pages
2023-01-12	423	2798323	10478	10478	26770465	26770465
2023-01-13	688	2799011	15464	25942	38953621	65724086
2023-01-14	774	2799785	15034	40976	38456559	104180645
2023-01-15	684	2800468	14076	55052	35789881	139970526

[SChernykh]

I've changed large page allocation messages back to mdebug (the same as it was before the refactoring in #8677)