Re: [[RFC][PATCH] v1 0/2] malloc/realloc with transparent huge page support

[Florian Weimer <fw@deneb.enyo.de>]

* Norbert Manthey:

> This change has been tested on top of glibc 2.23 in an Ubuntu 16.04
> environment for programs that benefit from huge pages due to their
> large memory usage and pseudo-random memory access patterns
> (e.g. SAT solvers, model checkers, optimization tools an
> others). More details on the performance improvements for these
> tools can be found in https://arxiv.org/abs/2004.14378, e.g. page 9.

Please show us the output of

$ cat /sys/kernel/mm/transparent_hugepage/enabled

from your test systems.  Thanks.

In the paper, you say this:

| Because there might be applications running on the host that would
| suffer from larger pages, THP is usually disabled on physical
| systems and it is not advised to set the value to always.

However, the default value for Red Hat Enterprise Linux 7 is, in fact,
"always", so it is puzzling why you see such a large benefit for
long-running processes.