|
sqlplus / as sysdba <<< "@ exclusive_latch.txt 'test excl. parent2 l0' 0 1 2 6" > /dev/null
[1] Done source peek.sh 'test excl. parent2 l0' 20 | timestamp.pl >|/tmp/peekx_${zdate}.txt
[4]- Done sqlplus / as sysdba <<< "@ exclusive_latch.txt 'test excl. parent2 l0' 0 3 4 6" > /dev/null
[5]+ Done sqlplus / as sysdba <<< "@ exclusive_latch.txt 'test excl. parent2 l0' 0 5 6 6" > /dev/null
[2]+ Done seq 20 | xargs -I{} echo -e 'sqlplus -s -l / as sysdba <<< @latch_free\nsleep 1' | bash >|/tmp/latch_freeo_${zdate}.txt
2.测试:
$ grep -v '^.*: $' /tmp/peekx_20190424091250.txt | cut -c10- | uniq -c
1 SYSDATE LADDR
1 ------------------- ----------------
1 2019-04-24 09:12:50 0000000060009978
1 Statement processed.
6 [060009978, 060009980) = 00000015 00000000
1 [060009978, 060009980) = 00000000 00000000
6 [060009978, 060009980) = 00000015 00000000
7 [060009978, 060009980) = 00000000 00000000
--//你可以发现第1个会话申请成功,第2个会话没有申请成功,直接退出.第3个会话申请成功(因为sleep 2+4.1秒).
--//cat /tmp/latch_freeo_20190424091250.txt
2019-04-24 09:12:50
2019-04-24 09:12:51
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=2 why=1, SID=295
2019-04-24 09:12:52
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=2 why=1, SID=295
2019-04-24 09:12:53
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=2 why=1, SID=295
2019-04-24 09:12:54
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=2 why=1, SID=295
2019-04-24 09:12:55
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=2 why=1, SID=295
2019-04-24 09:12:56
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=6 why=5, SID=295
2019-04-24 09:12:57
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=6 why=5, SID=295
2019-04-24 09:12:58
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=6 why=5, SID=295
2019-04-24 09:13:00
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=6 why=5, SID=295
2019-04-24 09:13:01
Process 21
holding: 0000000060009978 "test excl. parent2 l0" lvl=0 whr=6 why |