We are getting a lot of these errors in the catalina.log: java.lang.RuntimeException: java.lang.Null

[Tony Hart]

2019-01-30 17:07:16,292 http-8080-75 ERROR rivasro 1027x4110x8 1nn2vby 10.120.226.192 /secure/AssignIssue.jspa [atlassian.event.internal.EventPublisherImpl] There was an exception thrown trying to dispatch event 'com.atlassian.jira.event.issue.IssueEvent@a269a21[issue=FIMS-1164140,comment=<null>,worklog=<null>,changelog=[GenericEntity:ChangeGroup][id,5530928][author,rivasro][created,2019-01-30 17:07:16.285][issue,1523567],eventTypeId=3,sendMail=true,params={eventsource=action, baseurl=http://jira},subtasksUpdated=true]' from the invoker 'com.atlassian.event.internal.SingleParameterMethodListenerInvoker@486038e4'.
java.lang.RuntimeException: java.lang.NullPointerException

I believe this eventually hangs the system and start to recieve:

2019-01-30 16:17:39,482 http-8080-66 ERROR hernach 974x3364x26 zt7brc 10.78.5.98 /secure/WorkflowUIDispatcher.jspa [jira.issue.index.DefaultIndexManager] Wait attempt timed out - waited 30000 milliseconds
com.atlassian.jira.issue.index.IndexException: Wait attempt timed out - waited 30000 milliseconds
2019-01-30 16:19:01,424 main INFO [atlassian.plugin.loaders.ScanningPluginLoader] Plugin Unit: /var/atlassian/application-data/jira/plugins/.bundled-plugins/bndlib-0.0.255.jar (1329350530000) created
jira.index.lock.waittime : 30000
2019-01-30 16:42:09,260 main INFO [atlassian.plugin.loaders.ScanningPluginLoader] Plugin Unit: /var/atlassian/application-data/jira/plugins/.bundled-plugins/bndlib-0.0.255.jar (1329350530000) created
jira.index.lock.waittime : 30000
2019-01-30 16:52:38,750 main INFO [atlassian.plugin.loaders.ScanningPluginLoader] Plugin Unit: /var/atlassian/application-data/jira/plugins/.bundled-plugins/bndlib-0.0.255.jar (1329350530000) created
jira.index.lock.waittime : 30000

are there any workarounds for this?..

thanks.