280.View the Exhibit to examine the replay settings for replay parameters. What is the implication for
setting the values for replay parameters? (Choose all that apply.)
A. The COMMIT order in the captured workload is preserved during replay.
B. The value 100 in the THINK_TIME_SCALE parameter attempts to make the replay client shorten the
think time between calls.
C. The value 100 in the CONNECT_TIME_SCALE parameter attempts to connect all sessions as
captured.
D. The value 100 in the THINK_TIME_SCALE parameter attempts to match the captured user think time
while replaying.
E. The value 100 in the CONNECT_TIME_SCALE parameter attempts to connect all sessions
immediately as soon as the replay begins.
Answer: ACD
答案解析：
参考：http://blog.csdn.net/rlhua/article/details/14053709
官方参考：http://docs.oracle.com/cd/E11882_01/server.112/e41481/dbr_replay.htm#RATUG141
1.1.6.1 Preserving COMMIT Order
The synchronization parameter controls whether the COMMIT order in the captured workload will be preserved during replay.
If this parameter is set to SCN, the COMMIT order in the captured workload will be preserved during replay and all replay actions will be executed only after all
dependent COMMIT actions have completed.
If this parameter is set to OBJECT_ID, all replay actions will be executed only after all relevant COMMIT actions have completed. Relevant COMMIT actions
must meet the following criteria:
-
Issued before the given action in the workload capture
-
Modified at least one of the database objects for which the given action is referencing, either implicitly or explicitly
Setting this parameter to OBJECT_ID allows for more concurrency during workload replays for COMMIT actions that do not reference the same database objects during
workload capture.
You can disable this option by setting the parameter to OFF, but the replay will likely yield significant replay divergence. However, this may be desirable if the workload consists primarily of independent
transactions, and divergence during unsynchronized replay is acceptable.
11.1.6.2 Controlling Session Connection Rate
The connect_time_scale parameter enables you to scale the elapsed time between the time when the workload capture began and each session connects. You can use this option to manipulate the session
connect time during replay with a given percentage value. The default value is 100, which will attempt to connect all sessions as captured. Setting this parameter to 0 will attempt to connect all sessions immediately.
11.1.6.3 Controlling Request Rate Within a Session
User think time is the elapsed time while the replayed user waits between issuing calls within a single session. To control replay speed, use thethink_time_scale parameter to scale user think time
during replay.
If user calls are being executed slower during replay than during capture, you can make the database replay attempt to catch up by setting thethink_time_auto_correct parameter to TRUE.
This will make the replay client shorten the think time between calls, so that the overall elapsed time of the replay will more closely match the captured elapsed time.
If user calls are being executed faster during replay than during capture, setting the think_time_auto_correct parameter to TRUE will not change the think time.
The replay client will not increase the think time between calls to match the captured elapsed time.