perf(db): index the iMIP invitation scan - #13623
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/backport to stable5.11 |
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/backport to stable5.12 |
IMipService's cron (every ~300s) ran findIMipMessagesAscending, which filtered mail_messages on imip_message plus three flags with a sent_at window and ORDER BY sent_at. No index matched, so every run full-scanned the whole table (~944k rows) and filesorted, usually to return nothing. It was #2 by rows examined on a 903-account instance, 100% full scans. Add mail_msg_imip_idx (imip_message, sent_at): the rare imip_message value makes the leading column selective (1.45% of rows) and sent_at removes the filesort. The mutable flags (imip_processed, imip_error, flag_junk) are left out on purpose to avoid index churn; imip_message flips at most once. Registered via AddMissingIndicesEvent for existing installs and added to the 2022 message-index migration for new ones. Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Christoph Wurst <1374172+ChristophWurst@users.noreply.github.com> Signed-off-by: Daniel Kesselberg <mail@danielkesselberg.de>
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IMipService's cron (every ~300s) ran findIMipMessagesAscending, which filtered mail_messages on imip_message plus three flags with a sent_at window and ORDER BY sent_at. No index matched, so every run full-scanned the whole table (~944k rows) and filesorted, usually to return nothing. It was Nr 2 by rows examined on a 903-account instance, 100% full scans.
Add mail_msg_imip_idx (imip_message, sent_at): the rare imip_message value makes the leading column selective (1.45% of rows) and sent_at removes the filesort. The mutable flags (imip_processed, imip_error, flag_junk) are left out on purpose to avoid index churn; imip_message flips at most once. Registered via AddMissingIndicesEvent for existing installs and added to the 2022 message-index migration for new ones.
Assisted-by: Claude:claude-opus-4-8
^ applying the index on that instance shows how full table scans and sorts turn into simple index range scans.
Query time went from 300ms to 3ms.
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