Mekanism

Mekanism

Minecraft 1.20.1 / Forge: this page documents that build and its measurements. For the separate 205-control Minecraft 1.21.1 port, see Minecraft 1.21.1 NeoForge.

Two controls for Mekanism 1.20.1-10.4.13.69 (mod id mekanism), both working on the server (in single-player, the integrated server): radiation checks visit only the chunks that hold a radiation source, and items in logistical transporters find their place on long routes by index. Every switch checks the code it would change against the tested build; another build is left untouched with one WARN line (see How the patches are applied).

Key	Target	Side	Since	Kind
mekanism_radiation_source_range	Mekanism 1.20.1-10.4.13.69	BOTH	1.0.36	opt
mekanism_transporter_path_index	Mekanism 1.20.1-10.4.13.69	BOTH	1.0.36	opt

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mekanism_radiation_source_range

Since: 1.0.36 · Target: Mekanism 1.20.1-10.4.13.69 · Side: BOTH (acts on the server, incl. the integrated server) · Kind: opt

Mixin: RadiationManagerSourceRangeMixin

Mekanism radiation checks visit only the chunks that hold a source. About once a second for every living entity (and for players) Mekanism measures the radiation where it stands: it builds the 121 chunks around it with a set and a table view for each, almost always to find no source at all (sources exist only where radioactive gas was dumped or a reactor melted down). The check now looks only at chunks that hold a source: none in range gives the background level at once, exactly one is read as before; two or more, or a very large source table, run Mekanism's own walk. The numbers come out the same to the last bit, the radius-1 setting keeps its "centre chunk only" behaviour, and the random draw per entity, shielding, decay and the client updates around the check are unchanged.

Idea: Mekanism's own 1.20.4+ commit messages and Mekanism: Overclocked (radiation source index), idea text only

Measured: 320,154 checks bit for bit identical, 0 differences (shadow mode 246,986 / 0), Valkyrien Skies' radiation hook applied alongside. Per check: no sources 4.7 us and 14.8 KB -> 19 ns and 56 B; 20 sources in the world 5.6 -> 0.16 us; 500 sources 6.0 -> 2.4 us (Ryzen 9 3900X, interleaved medians). Here Chunk3D.expand was 3.0% of the integrated server thread's allocation.

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mekanism_transporter_path_index

Since: 1.0.36 · Target: Mekanism 1.20.1-10.4.13.69 · Side: BOTH (acts on the server) · Kind: opt

Mixin: TransporterStackPathIndexMixin

Mekanism transporter items find their place on long routes by index. An item travelling through logistical transporters looks up where the current transporter sits on its route several times per tick (next stop, previous stop, end of route, network updates), each time scanning the whole route. Routes of 16 or more transporters are now looked up in an index of the route, built once per route; shorter routes are scanned as before. Mekanism never changes a route in place (it only replaces it), so every answer is the one the scan gives, including routes that pass the same spot twice.

Idea: Mekanism: Overclocked (cached path index), idea text only

Measured: 144,001 route checks identical (next/previous/final, packet bytes, update NBT), shadow 936,001 / 0. Per trip along a route of 20 / 50 / 100 / 300 transporters 1.5x / 2.9x / 5.2x / 12.7x faster (Ryzen 9 3900X).