Re: remap the .text segment into huge pages at run time

Hi,

On 2023-06-20 10:29:41 -0700, Andres Freund wrote:
> On 2023-06-20 10:23:14 +0700, John Naylor wrote:
> > Here's a start at that, trying with postmaster only. Unfortunately, I get
> > "MADV_COLLAPSE failed: Invalid argument".
> 
> I also see that. But depending on the steps, I also see
>   MADV_COLLAPSE failed: Resource temporarily unavailable
> 
> I suspect there's some kernel issue. I'll try to ping somebody.

Which kernel version are you using? It looks like the issue I am hitting might
be specific to the in-development 6.4 kernel.

One thing I now remember, after trying older kernels, is that it looks like
one sometimes needs to call 'sync' to ensure the page cache data for the
executable is clean, before executing postgres.

Greetings,

Andres Freund