When you try to upgrade more than 160 ws in a single PM instalation a TO MANY CONNECTIONS ERROR happens, and this stop the ws upgrade.
When you make the upgrade of many ws, each ws opens a new connection to the DB, and this is closed only at the end of all ws upgrade, so this cause the TO MANY CONNECTIONS error.
To solve the problem I kill the connection to the DB at the end of each ws upgrade.
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