Disable fsync!

libeatmydata is a small LD_PRELOAD library designed to (transparently) disable fsync (and friends, like open(O_SYNC)). This has two side-effects: making software that writes data safely to disk a lot quicker and making this software no longer crash safe. DO NOT use libeatmydata on software where you care about what it stores. It’s called libEAT-MY-DATA for …

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Monitor mail queue with filter

check_mailq_filter – an Icinga / Nagios postfix mail queue monitor with a filter (include or exclude mails matching a pattern). So to exclude facebook mails from your monitor you may run: check_mailq_filter.py -x ‘.*facebookmail.*’ While you’re here, have a look at pfqueue – a console tool for interactively viewing your postfix queue that’s a step …

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Add tracking IDs to your web application

With a complex multi-tier stack with HTTP requests getting proxied it can be difficult to track a request as it goes around the system. One thing you can do is enable mod_unique_id in apache – this creates a distinct environment variable UNIQUE_ID in the web server context for each incoming request. Simply loading the module …

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