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Date: Wed, 5 Sep 2018 21:23:53 -0700
From: bob prohaska <fbsd@www.zefox.net>
To: "Rodney W. Grimes" <freebsd-rwg@pdx.rh.CN85.dnsmgr.net>
Cc: freebsd-arm@freebsd.org, bob prohaska <fbsd@www.zefox.net>
Subject: Re: RPI3 swap experiments (r338342 with vm.pageout_oom_seq="1024"
 and 6 GB swap)
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On Wed, Sep 05, 2018 at 07:43:52PM -0700, Rodney W. Grimes wrote:
> 
> What makes you believe that the VM system has any concept about
> the speed of swap devices?  IIRC it simply uses them in a round
> robbin fashion with no knowlege of them being fast or slow, or
> shared with files systems or other stuff.
>
 
Mostly the assertion that OOMA kills happening when the system had
plenty of free swap were caused by the swap being "too slow". If the
machine knows some swap is slow, it seems capable of discerning other
swap is faster. 

Thanks for reading!

bob prohaska