port-amd64/58217: Under heavy load, Xorg screen gets corrupted

[jmclists%jmcunx.com@localhost]

>Number:         58217
>Category:       port-amd64
>Synopsis:       Under heavy load, Xorg screen gets corrupted
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    port-amd64-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Apr 30 13:35:00 +0000 2024
>Originator:     John McCue
>Release:        10.0 amd64, Thinkpad T420
>Organization:
>Environment:
NetBSD neutron.jmcunx.com 10.0 NetBSD 10.0 (GENERIC) #0: Thu Mar 28 08:33:33 UTC 2024  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/amd64/compile/GENERIC amd64
>Description:
When a heavy process has run for a while, Xorg screen gets corrupted.  95% of the time exiting and restarting X will correct.  But artifacts will eventually reappear until the process ends.  Usually happens after the process has been executing for about 1 hour.

dmesg, Xlog.0.log and indent /netbsd is here:

    https://dmesgd.nycbug.org/index.cgi?do=view&id=7725

Screen print is here:

    https://www.jmcunx.com/data/jmcnetbsd.jpg

The issue occurs when verifying a sha256 using cksum(1) on a 43G Text File.  But other heavy processes that execute for a long time can cause the same problem.

>How-To-Repeat:
Start a heavy process that will run for more than an hour.

The easiest way is to verify a SHA256 cksum on a extremely File (see description above).

>Fix:
If I exit X and go back in, the issue will resolve itself.  But if the process is still executing, the artifacts will re-appear after a period of time.