找到原因了,oracle的bug
note 338461.1
Trying to invoke SQL*Plus hangs when machine uptime reaches 248 days.
Database connection is not relevant as the 'sqlplus' executable itself hangs with or without connection information. It hangs regardless of what parameters are passed in. For example:
....
Bug 4612267 OCI CLIENT IS IN AN INFINITE LOOP WHEN MACHINE UPTIME HITS 248 DAYS
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