This seems bad, Splunk advises you to turn off THP due its small read/write characteristics: https://help.splunk.com/en/splunk-enterprise/release-notes-a...
Bad because as of Splunk 10.x, Splunk bundles postgres to integrate with their SOAR platform. Parenthetically, this practice of bundling stuff with Splunk is making vuln remediation a real pain. Splunk bundles its own python, mongod, and now postgres, instead of doing dependency checking. They're going to have to keep doing it as long as they release a .tgz and not just an RPM. The most recent postgres vuln is not fixed in Splunk.