Hi Mick,
Thanks for the advice, setting the exclusions with
symcfg add -k '\Symantec Endpoint Protection\AV\Storages\FileSystem\RealTimeScan' -v HaveExceptionDirs -d 1 -t REG_DWORD
symcfg add -k '\Symantec Endpoint Protection\AV\Storages\FileSystem\RealTimeScan\NoScanDir' -v /path/to/mysql -d 1 -t REG_DWORD
did the trick!