Wait Event: Direct Path Writes

Wait Event: Direct Path  Writes

Possible Causes:

• These are waits that are associated with direct write operations that write data from users’ PGAs to data files or temporary tablespaces
• Direct load operations (eg: Create Table as Select (CTAS) may use this)
• Parallel DML operations
• Sort IO (when a sort does not fit in memory

Actions:

• If the file indicates a temporary tablespace check for unexpected disk sort operations.
• Ensure <Parameter:DISK_ASYNCH_IO> is TRUE . This is unlikely to reduce wait times from the wait event timings but may reduce sessions elapsed times (as synchronous direct IO is not accounted for in wait event timings).
• Ensure the OS asynchronous IO is configured correctly.
• Ensure no disks are IO bound

Ref:
WAITEVENT: "direct path write" Reference Note (Doc ID 50416.1)
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