Gantt chart relationships update slowly when there are a large number of relationships are in a project.

Steps to Reproduce

  1. Create a large project with multiple layers of dependencies.
  2. Update the project by changing the end date of one of the project tasks or deleting a dependency.

This triggers the ProjectGanttSchedulePage script include, which runs as an AJAX request. The script can run for over a minute depending on the number of relationships it must update. The following appears in the localhost logs:

2015-02-05 08:31:33 (441) Default-thread-283 88695D3D6F4E390064C989F1BE3EE4BF #1006075 /xmlhttp.do Parameters -------------------------





sysparm_table_name=planned_task sysparm_hashcode=1904000890

sysparm_span_id=c9a8035a0fbc7100918af2a362050e37 ...

2015-02-05 08:32:58 (044) Default-thread-283 88695D3D6F4E390064C989F1BE3EE4BF #1006075 /xmlhttp.do -- total transaction time: 0:01:24.614, total wait time: 0:00:00.000, session wait: 0:00:00.000, semaphore wait: 0:00:00.000, source:


If you are able to upgrade, review the Fixed In field to determine the versions that have a permanent fix to this issue.

After upgrading, schedule caching needs to be enabled through the settings (All Properties) below:

  • com.snc.project.schedule_cache = true (this property enables / disables schedule caching)
  • com.snc.project.schedule_cache_end = 2020 (defines the end year for the project schedule cache, for example, 2020)
  • com.snc.project.schedule_cache_start = 2009 (defines the start year for the project schedule cache, for example, 2009)

ServiceNow recommends keeping the difference between com.snc.project.schedule_cache_end and com.snc.project.schedule_cache_start less than 15 years. There is also an upper limit of 20 years on the cache, but the performance is best when it is less than 15 years.

Related Problem: PRB623213

Seen In

Eureka Patch 11 Hot Fix 2
Eureka Patch 4 Hot Fix 1
Eureka Patch 6
Eureka Patch 9
Eureka Patch 9 Hot Fix 1
Fuji Patch 2 Hot Fix 1

Fixed In

Eureka Patch 9 Hot Fix 1
Fuji Patch 2

Associated Community Threads

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Article Information

Last Updated:2017-03-15 08:40:03