⚡ Performance: Per-address N+1 and nested loops in Multishipping module

[lbajsarowicz]

Performance Issues in Magento_Multishipping

Findings

#	File	Line(s)	Issue	Consensus Severity
134	Model/Checkout/Type/Multishipping.php	640-642	N+1 Loading: addressRepository->getById() per address + collectAddressTotals() per address = N shipping method queries.	High (Claude+Gemini: Critical, Codex: High)
135	Model/Checkout/Type/Multishipping.php	730-733	Expensive Loop Ops: setCollectShippingRates(true) set per address in loop before single collectTotals().	Medium-High
136	Model/Checkout/Type/Multishipping.php	593, 633, 661	N+1 Loading: Three separate addressRepository->getById() calls in single method instead of single load and reuse.	Medium-High
137	Model/Checkout/Type/Multishipping.php	509-512, 521-524	Expensive Loop Ops: Nested loops in setShippingItemsQuotes() calling _addShippingItem() per item-address pair with getQuote() called repeatedly.	Medium-High

Methodology

• Static code analysis cross-validated by 3 AI systems (Claude, Codex gpt-5.4, Gemini 3 Pro)

[m2-assistant]

Hi @lbajsarowicz. Thank you for your report.
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[github-jira-sync-bot]

✅ Jira issue https://jira.corp.adobe.com/browse/AC-16863 is successfully created for this GitHub issue.