We don't have testing results for changes to this setting as it relates to the various possible environments that are possible for CA Performance Manager. The query plays a role in how much data it's trying to process as well which exponentially expands the testing that would be required due to the vast variety of possible queries and thus query result sizes that could be seen.
Without testing results to rely on it does come down to a small amount of trial and error.
Engineering notes that the OpenAPI has it's own resource pool that has a 2 minute runtime cap. Any query that takes more than 2 minutes will be killed via Vertica. We can try increasing the value and testing how long it takes at each level.
They recommend that we only go as high as 1 minute 30 seconds, leaving a 30 second buffer to handle larger requests that would come in from time to time.