Clarify swap descriptions #14480
Clarify swap descriptions #14480
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Could we configure this on a per-process basis? e.g. MemorySwapMax in systemd unit specifications? This might allow TiDB to not swap out but allow other things to be swapped out.
check-before-deployment.md
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| > - `sysctl -p` is to make the configuration effective without restarting the system. | ||
| ```bash | ||
| echo "vm.swappiness = 0">> /etc/sysctl.conf | ||
| swapoff -a |
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This is not sufficient. The swapoff -a command only disables the swap until the next reboot of the system. One also needs to remove this from /etc/fstab of mask the systemd unit for swap.
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https://rageagainstshell.com/2019/12/disable-swap-in-systemd/ has a good description for systemd based systems
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For now I would suggest to keep it closer to the original statement:
echo "vm.swappiness = 0">> /etc/sysctl.conf
sysctl -p
swapoff -a && swapon -aThis sets swappiness to 0 and then disables/enables swap to for things that have already been swapped out to be swapped back in.
If we leave swap disabled, but don't configure this in a way that survives a reboot this is like leaving a booby trap.
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Co-authored-by: Daniël van Eeden <github@myname.nl>
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What is changed, added or deleted? (Required)
Clarify confusing descriptions for disabling system swap
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