oltpxcset − Modify settings in an ongoing run
oltpxcset [-H --help] [-k key] [--key key] [--hostname name] ...
Change certain run parameters while a run using oltpxcrun is in progress. The key and the hostname are the primary keys of the table (rwlrun_xc) that saves the external control parameter, and these default to the RWLOLTP_NAME environment and the hostname of the system where oltpxcset is called.
If no parameters or only key and/or hostname are provided, the current values will be shown without doing any changes.
To do changes, provide one or more of the long options shown below.
-h|-H|--help
Print short help.
-k|--key key
Set the key that will be used when storing results in the repository database. The default is the same as the project name, i.e. the RWLOLTP_NAME environment.
--hostname name
Set the hostname. The default is the name of the host where oltpxcset is called.
--ratefactor D
Set a multiplier for the arrival rate of the emulated business transactions. Any double value higher than 0 is accepted, but high values may lead to overload.
--loadfactor D
Set the proportion of worker threads that will be active. Any double value between 0 and 1 are accepted.
--hardparse N
Set to a value between 0 and 2. The value is a probability that some emulated business transactions are using SQL statements with literal values in stead of place-holders and therefore are hard parsed.
--parsefailure N
Set to a value between 0 and 1. The value is a probability that some emulated business transactions are using SQL statements that cause a parse failure during execution.
--ignore-parsefailure N
Set to 0 or 1. If set to 1, and the next oltpxc execution uses parse failures, the actual ORA- error will be suppressed in the stderr output.
--logoffrate D
Specify the proportion of sessions that when returned to the session pool, also will be forced to log off from the database. Set to a value between 0 and 1. Suggested values are around 0.1 to 0.2 and values close to 1 will cause very high database logon rates.
--minpool N
--maxpool N
Change either of the minimum or maximum pool size of the session pool in each worker thread.
--cursorleak D
Set the proportion of cursors that will be leaked. The value is a double value between 0 and 1, 0 meaning no leak. Any non-zero value will cause an eventual ORA-01000 error, the higher the value the faster the ORA-01000 errors will occur. If you have set a non-zero value and observe ORA-01000 errors, you can change the value back to 0 and the ORA-01000 errors will disappear after some time.
--sessionleak D
Set the proportion of sessions that will be leaked. The value is a double value between 0 and 1, 0 meaning no leak. Any non-zero value will cause sessions to become blocked an unavailable, and may eventually cause the run to get into an unrecoverable state. Any non-zero value should be small and used with care.
--cursorcache N
Set the size of the cursor (statement) cache. The lowest allowable value is 1, which will cause almost all executes to also imply a (soft) parse.
--badplan N
Set the number of queries in the awindex_query transaction that uses a full table scan rather than an index. The value must be in the range 0..10.
--cpusec D
Set the number of seconds each of the frequently executed transactions will be a cpu hog while it has a session.
--waitsec D
Set the number of seconds each of the frequently executed transactions will be waiting doing nothing while it has a session.
--proccount N
Set a process count to be used by the next run.
--stopnow
Abort one run prematurely. This will be done without cleanup, but a new run will be started shortly after when using oltpxcrun.
--finishnow
Abort current run prematurely and also stop oltpxcrun.
--finishnext
Wait for the current run to complete normally and then finish oltpxcrun.
--nopool
--yespool
When the next run starts, it will be using dedicated connections respectively session pool; the latter is the default.
--default
Set all values to their defaults.
--no-show
Do not show all values after modifications have been done.
The command is supposed to be used as part of a demonstration together with various other live displays of values such as DBCPU, DBTIME, contention, etc. You will need to gain experience with the various settings to understand the implications.
It is highly recommended that you use this in combination with oltpxcrun having long runtimes. When starting oltpxcrun, make sure to redirect stderr to a place (e.g. via tail -f of a file) that can be shows as part of the demonstration.
The options for leaking, in particular sessionleak, should be used with care. Do not use the command against a production database.
At present, the parameters cursorleak, sessionleak, logoffrate, hardparse and parsefailure only have actual impact on a subset of emulated business transactions.
The primary purpose of external control is for internal use by the Oracle Real World Performance team.
Changes, including changes that are incompatible with ealier versions of external control should be expected.
Not everything is described and some description is inaccurate.
Copyright
© 2023 Oracle Corporation
Licensed under the Universal Permissive License v 1.0 as
shown at https://oss.oracle.com/licenses/upl
oltp(2rwl), oltpcore(2rwl), oltprun(2rwl)