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I got a problem where a session WAIT's for "log file sync" + "latch free" forever and REDO LOGS never get switched. If I manually switch the logs (ALTER SYSTEM SWITCH LOGFILE) the "switch" succeeds but it doesn't help the session WAITs.
V$SESSION_WAIT (waits are either "latch free" or "log file sync"
EVENT P1TEXT P1
------------------------- ------------------------- ---------
log file sync buffer# 38 EVENT P1TEXT P1
------------------------- ------------------------- ---------
latch free address 805363076
When "log file sync" waits occur P1 increments by 1 with intervals of 3-5 seconds then eventually "latch free" wait occurs (P1 for "latch free" is always same = 805363076). Below is the summary for waits/timeouts.
V$SESSION_EVENT
SID EVENT TOTAL_WAITS TOTAL_TIMEOUTS --------- ----------------------------------- ----------- -------------- 23 latch free 1618 957 23 process startup 4 0 23 rdbms ipc reply 29 0 23 enqueue 18 0 23 free buffer waits 14 0 23 local write wait 3 0 23 log buffer space 568 0 23 log file switch completion 259 27 23 log file sync 116801 212 23 db file sequential read 355 0 23 db file scattered read 396 0 23 file open 6 0 23 SQL*Net message to client 87 0 23 SQL*Net message from client 87 0 23 PX Deq: Join ACK 27 0 23 PX Deq: Signal ACK 27 12 23 PX Deq: Parse Reply 17 0 23 PX Deq: Execute Reply 1401 0
18 rows selected.
Please help guys! Never seen this before. Received on Tue Jan 30 2001 - 14:01:13 CST