OVERHEAD

Check ya defaults!

Linux

Whether it’s a sysctl hardening setting, or some optimised mount option you read about in an article from 2010, you’re probably specifying options which are already the default, setting options already implied by another option, or you’re not specifying an option wrongly assuming it’s the default.

For example, you:

  • Don’t need to specify space_cache=v2 for BTRFS since btrfs-progs v5.15 (for newly made filesystems at least).
  • Don’t need to specify noatime and nodiratime at the same time (noatime implies nodiratime).
  • Don’t need to set net.ipv4.tcp_syncookies=1 (or many other sysctl options, check with sysctl name-of-option first)
    • Or, kernel.perf_event_paranoid=3 is being ignored (since values above 2 are handled by a custom kernel patch).
  • Should be using perf-no_read_workqueue & perf-no_write_workqueue with LUKS when using an SSD (seriously, it’s free performance, like, half the latency; twice the throughput kinda performance).
    • Run cryptsetup --perf-no_read_workqueue --perf-no_write_workqueue --persistent refresh /path/to/disk to persistently set it on a running system.

And many other defaults you haven’t checked!

CHECK YA DEFAULTS!!!

…Please?