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#imap
2 posts
Systems debugging
6 minA Dovecot optimization the compiler had been deleting all along
An IMAP THREAD command was panicking inside Dovecot's array code. The crash was real, but the comment above it described an optimization that hadn't run in any -O2 build ever shipped. ATTR_PURE turned it into dead code, and the same annotation decided which line showed up in the backtrace.
#dovecot#c#imap#debugging
Systems debugging
5 minYou cannot average percentiles
Finding an IMAP server's real capacity means driving load from many hosts at once. The hard part isn't generating the load. It's combining their latencies into one honest P99 without quietly lying about it.
#imap#benchmarking#statistics#performance