On the "Big Sur" release of MacOS (OSx v11.x), the increased security means shared memory configuration, as required for large GemStone installations, has become more restrictive. Setting values in /etc/sysctl.conf is no longer effective.
As root, you can manually change the shared memory parameters using /usr/sbin/sysctl; however, changes made in this way are lost on reboot.
To upgrade the configurations permanently, you must set the configuration values in an XML-formatted file with the path and name:
/Library/LaunchDaemons/com.gemtalksystems.shared-memory.plist
You will need to reboot, for the settings to take effect.
An example plist file for a host with 8 GB of RAM is available at com.gemtalksystems.shared-memory.plist, with the contents below; edit the settings as appropriate for your machine RAM and GemStone configuation.
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>Label</key> <string>shmemsetup</string> <key>UserName</key> <string>root</string> <key>GroupName</key> <string>wheel</string> <key>ProgramArguments</key> <array> <string>/usr/sbin/sysctl</string> <string>kern.sysv.shmmax=6442450944</string> <string>kern.sysv.shmall=1572864</string> </array> <key>KeepAlive</key> <false/> <key>RunAtLoad</key> <true/> </dict> </plist>
Last updated: 9/11/23