RE: Transparent HugePages causing crashes?

The part that disappoints me more is that they refer to the note covering 'standard' hugepages without any details to let us know if we are at risk of this transparent hugepage instability in the following situation:

• Transparent hugepages left at default 'enabled' state
• Standard hugepages configured via vm.nr_hugepages as per note 361323.1 and used by the database

Also, they refer to disabling transparent hugepages at boot time but do not discuss whether or not one can safely set these to 'never' on an active, running server where standard hugepages are in active use, implying a reboot will be needed without stating so.

> From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On
> Behalf Of John Hurley
>
> Classic oracle support information here ... they give a fix that refers to a
> directory that does not exist. Who would QA a support alert?
>
> First the directory ( on 6.4 anyhow ) is /sys/kernel/mm/transparent_hugepage
> NOT ( ... hugepages ).
>
> Plus they do not note that directory name is also different between release
> levels ( 6.2 versus 6.4 ) etc.
>
> Caveat emptor.
>
>
> if test -f /sys/kernel/mm/transparent_hugepages/enabled; then
> echo never > /sys/kernel/mm/transparent_hugepages/enabled
> fi
> if test -f /sys/kernel/mm/transparent_hugepages/defrag; then
> echo never > /sys/kernel/mm/transparent_hugepages/defrag
> fi

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