Lazy index loading in Dovecot for large mailboxes
Learn how Dovecot’s lazy index loading uses mmap to speed up IMAP startup, how to tune cache size, and when to rebuild a stale index.
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How to mmap() a large file without risking the OOM killer?
I've got an embedded ARM Linux box with a limited amount of RAM (512MB) and no swap space, on which I need to create and then manipulate a fairly large file (~200MB). Loading the entire file into RAM, modifying the contents in-RAM, and then writing it back out again would sometimes invoke the OOM-killer, which I want to avoid. My idea to get around this was