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    Name:    globlcks.sql

    Author:  Mark Gurry

    The following query shows the number of global locks. If you are 
    tuning parallel server and see no reduction in the figures below, 
    you are wasting your time tuning further.

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SELECT substr(name, 1, 25), COUNT(*) 
  FROM v$sysstat
 WHERE name LIKE 'global%'
    OR name LIKE 'nxt scns gotten%';