ServiceNow Learning 167: Important point to remember while updating System property.

[Shamma Negi]

Hi All,

Today I will cover the importance of setting the value of clear cache to "True" while updating or creating a new property in ServiceNow.

Ignore Cache Checkbox

ServiceNow system stores all "sys_properties" values in server-side caches so that querying the database for config settings can be avoided. When we update the value of any system property in an ServiceNow Instance, the system always flushes the cache. By default, this checkbox is set to false.

If we check this field or make it true, then we decide that the system should prevent the cache flush

Note: If we create or update any system property wherein the clear cache is unchecked it comes under system scan report.

Question: What will happen if the ignore cache checkbox is false?

Answer: Setting this property to false can lead to slowness in the system. This can happen anytime and can take some time to make it back to normal.

Question: Why do we see the slowness in the system?

Answer:  If anyone changes a custom system property in which the "Ignore cache is set to false".

Because the flag was false, then when the system property was updated, it will cause a cache flush. The cash flush makes slowness in all the instance for a while until the cache was rebuilt.

Question: What can be done to avoid this performance issue?

Answer: Make sure if anyone changes or creates a new property then they have to set the "Ignore Cache" to true so that it doesnt impact the performace and also doesnt come in Instance Scan. So as to follow the ServiceNow best practice.

Hope this helps you!

Pease mark this helpful.

Regards,

Shamma