A launchd agent (put it in ~/Library/LaunchAgents) to stop simulator Spotlight processes

com.dqd.stop-simulator-spotlight.plist

<?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>com.dqd.stop-simulator-spotlight</string>
    <key>ProcessType</key>
    <string>Background</string>
    <key>ProgramArguments</key>
    <array>
        <string>/bin/sh</string>
        <string>-c</string>
        <string>/bin/ps -wwxo 'pid state command' | /usr/bin/grep '/CoreSimulator/.*/Spotlight$' | /usr/bin/awk '$2 ~/^[^T]/ { print $1 }' | /usr/bin/xargs /bin/kill -STOP</string>
    </array>
    <key>StartInterval</key>
    <integer>10</integer>
</dict>
</plist>

Xcode 13's simulator starts a Spotlight process that continuously spews errors to the system log. This is still happening as of at least Xcode 13.2 beta 1.

This launchd agent looks for simulator Spotlight processes every 10 seconds, and sends them SIGSTOP if they're not already stopped.

Put the file in ~/Library/LaunchAgents, then either reboot or run this:

launchctl load ~/Library/LaunchAgents/com.dqd.stop-simulator-spotlight.plist