Performance Degradation with rsync in container or cgroupv2 with MEM limit

[Alexandru Lazarev]

hi Greg,
Thx for Your feedback - I would appreciate any feedback.

I'am not paying for it - I am doing some tests on a given platform.
Kernel is RHCK.
I posted this question-issue here because maybe it is some generic
kernel issue (I saw several of unanswered threads on various platforms
of rsync degradation in containers) amnd someone can suggest to me
right directions, OR..
I know here in mail list are some people from Red Hat and Oracle which
usually provide their valuable answered, so I am still keep my hopness
on finding some ideas on this issue

On Wed, Mar 26, 2025 at 4:00 PM Greg KH <greg at kroah.com> wrote:
>
> On Wed, Mar 26, 2025 at 02:11:41PM +0200, Alexandru Lazarev wrote:
> > Hi everyone,
> > I'm experiencing a significant performance degradation when using
> > "rsync" to copy files over the network from within a container or
> > cgroup with memory limits on Oracle Linux 9.2. The issue occurs with
> > the Red Hat Compatible Kernel (RHCK) 5.14.0-284.11.1.el9_2.x86_64 but
> > not with the Unbreakable Enterprise Kernel (UEK)
> > 5.15.0-101.103.2.1.el9uek.x86_64.
>
> <snip>
>
> As you are paying for Oracle support for these kernels, please contact
> them to take advantage of that support.  They are the only ones that can
> help you out here as no one in the community has any idea of what is in
> these kernels at all, sorry.
>
> good luck!
>
> greg k-h