Full error message:
WARNING: /{sitelocation redacted}/libs/Zend/Db/Statement/Pdo.php(228): Warning - Error while sending QUERY packet. PID=18591 - Piwik 2.14.3
I did search, the most recent hit was in German from 15 days ago and the most recent before that was > 4 months.
Reloaded piwik by clicking the “refresh” button in Chrome Version 45.0.2454.85 (64-bit) (Mac OS X 10.10.5) (piwik install running on Linux)