Thread: 18.4.4. Linux huge pages

18.4.4. Linux huge pages

From
piotrwlodarczyk89@gmail.com
Date:
The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/9.6/static/kernel-resources.html
Description:

Hi,

it's a mistake in 18.4.4. Linux huge pages (also in 9.4 and 9.5
documentation). Example how to count number f huge pages says:

6490428 / 2048 (PAGE_SIZE is 2MB in this case) are roughly 3169.154 huge
pages, so you will need at least 3170 huge pages:

It's very rare that PAGE_SIZE is 2MB. It's more common situation that the
value is 4096KB. But it's not a problem.

The VmPeak should by divded not by PAGE_SIZE but by Hugepagesize listed by
cat /proc/meminfo | grep Hugepagesize. 



Re: 18.4.4. Linux huge pages

From
Andrew Kerber
Date:
In most versions of Linux, the default hugepage size is 2m. Other Unix versions may have different hugepage sizes, e.g.
AIX,but Linux defaults to 2m  

Sent from my iPad

> On Oct 21, 2016, at 11:43 AM, piotrwlodarczyk89@gmail.com wrote:
>
> The following documentation comment has been logged on the website:
>
> Page: https://www.postgresql.org/docs/9.6/static/kernel-resources.html
> Description:
>
> Hi,
>
> it's a mistake in 18.4.4. Linux huge pages (also in 9.4 and 9.5
> documentation). Example how to count number f huge pages says:
>
> 6490428 / 2048 (PAGE_SIZE is 2MB in this case) are roughly 3169.154 huge
> pages, so you will need at least 3170 huge pages:
>
> It's very rare that PAGE_SIZE is 2MB. It's more common situation that the
> value is 4096KB. But it's not a problem.
>
> The VmPeak should by divded not by PAGE_SIZE but by Hugepagesize listed by
> cat /proc/meminfo | grep Hugepagesize.
>
>
>
> --
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