Solaris 11.4 hosted repository, TortoiseHG clone attempt consumes all resources

[Scott Newman - NOAA Affiliate]

Good morning everyone!

We are currently using Mercurial 5.2.2 hosted on Solaris 11.3 and accessed
by contributors via TortoiseHG 5.0.2 from their Windows Desktops.  We are
in the process of migrating applications to new hosts running Solaris
11.4.  When trying to clone a copy of the repository hosted on Solaris
11.4 the clone runs very slowly and the process consumes most of the
memory (64GB) on the host, starts generating "-bash: fork: Resource
temporarily unavailable" errors for users on the box after about 2
minutes, and the clone process fails with a " Server Unexpectedly closed
connection" message.  The same process on Solaris 11.3 has a negligible
impact on resources and finishes in about 10 minutes.

I have spent several days with the Network and Systems Administrators
trying to resolve this issue without success.  We tried many things,
including adjusting resource configurations, rebuilding Mercurial and
Python, using Mercurial and Python from the working server, using the
pre-built package from Oracle (v4.9.1),

Any insight into what might be happening or how to further troubleshoot,
mitigate, or remediate would be appreciated.

I will be posting a similar message to TortoiseHG once I can find a place
to do so.

Thank you in advance for taking the time to review my request and please
know that any assistance would be appreciated.

Scott