The noclear parameter for sp_sysmon and improvements to the monitor counter concurrency enable you to run multiple concurrent sessions of the sp_sysmon and other monitoring applications, such as Monitor Server, Historical Server or other sp_sysmon sessions.
When you include the noclear option in sp_sysmon, sp_sysmon does not zero out the monitor counters. As a result, data collected by other applications using the monitor counters at the same time are not affected by the sp_sysmon report.
When used with the noclear parameter, sp_sysmon utilizes a temporary table. If space in a user’s default temporary database is limited, you may need to increase the size of the database to run sp_sysmon with noclear.
The report contents generated from sp_sysmon with or without the noclear should be the same. However, the sp_sysmon report may show a small amount of additional server activity when run with the noclear parameter.
A field called “Sample Mode” has been added to the sp_sysmon report header to indicate whether the report was generated using “No Clear” or “Reset Counters” mode. The report header includes the labels “Sampling Started at” and “Sampling Ended at” when run with the noclear parameter. It displays “Statistics Cleared at” and “Statistics Sampled at” when run without the noclear parameter.
When noclear is used with a specific sample interval, for any parameter in the sp_sysmon, the command runs in noclear mode. If noclear is not specified, sp_sysmon clears the counters.
sp_sysmon interval [, noclear,[,section [, applmon]]]
Report usage without clearing the counters:
sp_sysmon "00:01:00", kernel, noclear
sp_sysmon "00:01:00", noclear
You can use noclear only when you
specify a sample interval in sp_sysmon.
If you specify begin_sample or end_sample,
you cannot use noclear.
