Major With increasing number of slaves the performance of the build node column display seems to decrease significantly.
In our setup, after increasing number of Slave from 7 to 18, all views that are showing the "Last Build Node" column took more than double time to show.
For example a view containing approximately 70 jobs took about 15 seconds to show with 7 slaves and 55 seconds with 18 slaves.
Monitoring the CPU load (Prcoess Explorer and Jenkins Melody Monitor Plugin) shows a fully loaded CPU-core for the request.
After completely removing the "Last Build Node" column, the same view appears in less than a second.
The number of jobs obviously also has an impact (i.e. a view with 20 jobs and "Last Build Node" column shows in about 5 seconds). But the impact of the number of Slaves seems to be much higher.
I didn't test if the number of Offline versuse Online slaves has an impact.
[JENKINS-21870] 'Build-Node-Column: Performance decreases when number of slaves increase
Code changed in jenkins
User: Fred G
Path:
src/main/java/jenkins/plugins/extracolumns/LastBuildNodeColumn.java
src/main/resources/jenkins/plugins/extracolumns/LastBuildNodeColumn/column.jelly
src/main/resources/jenkins/plugins/extracolumns/LastBuildNodeColumn/columnHeader.jelly
src/main/resources/jenkins/plugins/extracolumns/LastBuildNodeColumn/columnHeader_de.properties
src/main/resources/jenkins/plugins/extracolumns/LastBuildNodeColumn/config.jelly
src/main/resources/jenkins/plugins/extracolumns/LastBuildNodeColumn/config_de.properties
src/main/resources/jenkins/plugins/extracolumns/Messages.properties
src/main/resources/jenkins/plugins/extracolumns/Messages_de.properties
http://jenkins-ci.org/commit/extra-columns-plugin/3a95245926f7abb3075f2a63e413480121f70f5d
Log:
Add LastBuildNodeColumn
Replaces Build Node Column Plugin by Takahisa Wada, includes potential
fix for JENKINS-21870
Fred G
added a comment - I've migrated the last build node column to the Extra Columns Plugin (version 1.16+) and added a potential fix for this issue. Please test and report back if you still see a performance issue with the new column.
Fred G
added a comment - I've migrated the last build node column to the Extra Columns Plugin (version 1.16+) and added a potential fix for this issue. Please test and report back if you still see a performance issue with the new column. 
Kurt
added a comment - Thanks for the fix!
I've added Build-Node columns to plenty of our (sectioned) views. In the meantime we've also have increased number of slaves to >30.
No impact to performance can be noticed at all any more. The views showing up instantaneously just as without build node column.
Kurt
added a comment - Thanks for the fix!
I've added Build-Node columns to plenty of our (sectioned) views. In the meantime we've also have increased number of slaves to >30.
No impact to performance can be noticed at all any more. The views showing up instantaneously just as without build node column. 
Seems to be unrelated to core.