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The EVM CoreISSUE #8 of 48

eip-4844 · blob transactions · proto-danksharding

SoliaVSThe Reentrancy Reaper
Solia saysEIP-4844 added blob transactions — 128-KB binary payloads with their own exponential fee market — giving rollups cheap, ephemeral data availability.

EIP-4844 (proto-danksharding) introduced a new transaction type carrying up to six 128-KB blobs. Blobs are NOT accessible to the EVM but their KZG commitments are; rollups post compressed transaction data as blobs and prove its availability cheaply. Blob data is dropped from consensus nodes after ~18 days, so it is durable enough for fraud-proof windows but cheap enough to commoditize rollup DA.

The blob fee market is separate from gas. A blob_base_fee follows an exponential update: each block above the 3-blob target raises the fee multiplicatively, each block below lowers it. The demo simulates the multiplier across a varying blob load.

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Boss battleSimulate the blob_base_fee multiplier across seven blocks with blob counts varying from 0 to 6.

Example code

<!doctype html><html><head><meta charset="utf-8"></head>
<body style="background:#06040d;color:#e6e0ff;font-family:monospace;padding:20px"><pre id="o"></pre>
<script>
const TARGET_BLOBS = 3;
const MAX_BLOBS = 6;
const BLOB_KB = 128;
let excess = 0;
const blockBlobs = [6, 5, 4, 3, 2, 1, 0];
const rows = [];
for(const b of blockBlobs){
  const mult = Math.pow(1.125, excess / 3);
  rows.push('  block has ' + b + ' blobs  excess=' + String(excess).padStart(2) + '  blob_base_fee multiplier ≈ ' + mult.toFixed(3));
  excess = Math.max(0, excess + (b - TARGET_BLOBS));
}
document.getElementById('o').textContent = [
  'EIP-4844 blob transactions:',
  '  max blobs/block: ' + MAX_BLOBS + '   target: ' + TARGET_BLOBS,
  '  blob size: ' + BLOB_KB + ' KB (32 field-elements × 4096)',
  '  blob_base_fee = its OWN exponential market',
  '',
  ...rows,
  '',
  'blobs expire from CL nodes after ~18 days → cheap, ephemeral DA for rollups'
].join('\n');
</script></body></html>
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