[cron] sleep random seconds (<59), if not interactive or forced #5215
+6
−1
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#944 (comment)
A Let's Encrypt employee said in the comments "we do see peaks at the beginning of minutes and even seconds; the finer-grained time randomization, the better."
This adds a random amount of sleep seconds before beginning the cron job. I considered reading from
/dev/urandom
and so on, but we aren't doing anything security critical here so I thought that just using the process number modulo 59 (the largest prime <= 60) should give decent variability across the systems. The starting hour and minute are already randomized during the installation.