During my stability test for pssd(see details in the following email excerpt), I found that the more existing policies in the PDP, the more time to get the newly created policies to be shown in PDP. 

Please find the relationship of the time for a newly created policy to be available in PDP and the existing policy number in PDP in the following figure.

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Hi Guys,

I’m tring to do a full stability test for policy distribution https://wiki.onap.org/display/DW/72+Hours+Stability+Test+Plan+of+Policy+SDC+Service+Distribution . However, I met some issues and I need some help or suggestions.

My original stability test scenario is listed as https://wiki.onap.org/display/DW/72+Hours+Stability+Test+Plan+of+Policy+SDC+Service+Distribution#id-72HoursStabilityTestPlanofPolicySDCServiceDistribution-TestPlan , basically speaking it’s a continuous loop of 3 steps:

1. If there is existing policy in the pdp which corresponding to the csar files we’re about to generate, delete it from both pdp and pap
2. Generate a random csar and put it into the directory the policy-distribution is monitors, from there, the policy distribution will detect the newly added csar file and start parse it and generate policies and store into pap/pdp (the random csar we generated ensures that each will results different policy name)
3. Repeatedly trying to get the corresponding policy from pdp until success or retry count exceed

However, currently I’m setting the retry count to 20 and the wait time between each retry is 1 second in step 3, but there is quite some possibility that step 3 failed due to retry count exceeding. Though I can get most of the failed policy successfully back from pdp if I wait enough time. And when the error occues, I find the mariadb docker output the following:

mariadb | 2018-11-15 16:46:29 139701533542144 [Warning] Aborted connection 459 to db: 'onap_sdk' user: 'policy_user' host: '172.18.0.6' (Got timeout reading communication packets)
mariadb | 2018-11-15 17:26:49 139701534148352 [Warning] Aborted connection 294 to db: 'onap_sdk' user: 'policy_user' host: '172.18.0.4' (Got timeout reading communication packets)

Also find in the pdp error.log it shows exceptions caused by db connection broken.

I think waiting for 20 seconds for the policy to be shown in pdp is definitely enough because here we don’t have a heavy load. Should I increase the retry count and wait time in step3 or have I missed some configuration items in pdp/pap? I just used docker-compose in policy/docker repo to setup the pap/pdp.