Uppercase names in JIRA browse users feature caused slowness

"http-bio-8443-exec-244" daemon prio=10 tid=0x000000001589e800 nid=0x12b8 runnable [0x00002b1092e7e000]
   java.lang.Thread.State: RUNNABLE
	at java.lang.String.toLowerCase(String.java:2411)
	at java.lang.String.toLowerCase(String.java:2524)
	at com.atlassian.jira.bc.user.search.UserMatcherPredicate.apply(UserMatcherPredicate.java:42)
	at com.atlassian.jira.bc.user.search.UserMatcherPredicate.apply(UserMatcherPredicate.java:15)
	at com.atlassian.jira.bc.user.search.DefaultUserPickerSearchService.findUsers(DefaultUserPickerSearchService.java:96)
	at com.atlassian.jira.bc.user.search.DefaultUserPickerSearchService.findUsers(DefaultUserPickerSearchService.java:51)
	at sun.reflect.GeneratedMethodAccessor1596.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at com.atlassian.multitenant.impl.MultiTenantComponentFactoryImpl$AbstractMultiTenantAwareInvocationHandler.invokeInternal(MultiTenantComponentFactoryImpl.java:181)
	at com.atlassian.multitenant.impl.MultiTenantComponentFactoryImpl$MultiTenantAwareInvocationHandler.invoke(MultiTenantComponentFactoryImpl.java:211)
	at com.sun.proxy.$Proxy160.findUsers(Unknown Source)
...

"http-bio-8443-exec-188" daemon prio=10 tid=0x000000001842b800 nid=0xd41 runnable [0x00002b107bd21000]
   java.lang.Thread.State: RUNNABLE
	at java.lang.String.toLowerCase(String.java:2411)
	at com.atlassian.crowd.embedded.impl.IdentifierUtils.toLowerCase(IdentifierUtils.java:42)
	at com.atlassian.jira.crowd.embedded.ofbiz.OfBizInternalMembershipDao.isUserDirectMember(OfBizInternalMembershipDao.java:75)
	at com.atlassian.jira.crowd.embedded.ofbiz.OfBizDelegatingMembershipDao.isUserDirectMember(OfBizDelegatingMembershipDao.java:65)
	at com.atlassian.crowd.directory.AbstractInternalDirectory.isUserDirectGroupMember(AbstractInternalDirectory.java:678)
	at com.atlassian.crowd.directory.DelegatedAuthenticationDirectory.isUserDirectGroupMember(DelegatedAuthenticationDirectory.java:545)
	at com.atlassian.crowd.manager.directory.DirectoryManagerGeneric.isUserDirectGroupMember(DirectoryManagerGeneric.java:694)
	at com.atlassian.crowd.manager.directory.DirectoryManagerGeneric.isUserNestedGroupMember(DirectoryManagerGeneric.java:877)
	at com.atlassian.crowd.manager.application.ApplicationServiceGeneric.isUserNestedGroupMember(ApplicationServiceGeneric.java:1404)
	at com.atlassian.crowd.embedded.core.CrowdServiceImpl.isUserMemberOfGroup(CrowdServiceImpl.java:261)
	at com.atlassian.crowd.embedded.core.CrowdServiceImpl.isUserMemberOfGroup(CrowdServiceImpl.java:266)
	at com.atlassian.crowd.embedded.core.DelegatingCrowdService.isUserMemberOfGroup(DelegatingCrowdService.java:70)
	at com.atlassian.crowd.embedded.core.FilteredCrowdServiceImpl.isUserMemberOfGroup(FilteredCrowdServiceImpl.java:227)
	at com.atlassian.jira.security.roles.actor.GroupRoleActorFactory$GroupRoleActor.contains(GroupRoleActorFactory.java:94)
	at com.atlassian.jira.security.roles.CachingProjectRoleAndActorStore$CachedDefaultRoleActors.contains(CachingProjectRoleAndActorStore.java:510)
	at com.atlassian.jira.notification.type.ProjectRoleSecurityAndNotificationType.hasPermission(ProjectRoleSecurityAndNotificationType.java:169)
	at com.atlassian.jira.permission.DefaultPermissionSchemeManager.hasSchemePermission(DefaultPermissionSchemeManager.java:508)
	at com.atlassian.jira.permission.DefaultPermissionSchemeManager.hasPermission(DefaultPermissionSchemeManager.java:467)
	at com.atlassian.jira.permission.DefaultPermissionSchemeManager.hasSchemeAuthority(DefaultPermissionSchemeManager.java:414)
	at com.atlassian.jira.security.AbstractPermissionManager.hasProjectPermission(AbstractPermissionManager.java:240)
	at com.atlassian.jira.security.AbstractPermissionManager.hasPermission(AbstractPermissionManager.java:167)
	at com.atlassian.jira.security.AbstractPermissionManager.hasPermission(AbstractPermissionManager.java:152)
	at sun.reflect.GeneratedMethodAccessor290.invoke(Unknown Source)
...

"http-bio-8443-exec-225" daemon prio=10 tid=0x0000000016675000 nid=0x10fa runnable [0x00002b1090e5e000]
   java.lang.Thread.State: RUNNABLE
	at java.lang.String.toLowerCase(String.java:2411)
	at com.atlassian.crowd.embedded.impl.IdentifierUtils.toLowerCase(IdentifierUtils.java:42)
	at com.atlassian.crowd.embedded.api.UserComparator.hashCode(UserComparator.java:106)
	at com.atlassian.jira.crowd.embedded.ofbiz.OfBizUser.hashCode(OfBizUser.java:129)
	at java.util.HashMap.hash(HashMap.java:366)
	at java.util.HashMap.put(HashMap.java:496)
	at java.util.HashSet.add(HashSet.java:217)
	at com.atlassian.jira.user.util.UserUtilImpl$1.create(UserUtilImpl.java:149)
	at com.atlassian.jira.user.util.UserUtilImpl$1.create(UserUtilImpl.java:135)
	at com.atlassian.util.concurrent.ResettableLazyReference$InternalReference.create(ResettableLazyReference.java:143)
	at com.atlassian.util.concurrent.LazyReference$Sync.run(LazyReference.java:326)
	at com.atlassian.util.concurrent.LazyReference.getInterruptibly(LazyReference.java:146)
	at com.atlassian.util.concurrent.LazyReference.get(LazyReference.java:115)
	at com.atlassian.util.concurrent.ResettableLazyReference.get(ResettableLazyReference.java:89)
	at com.atlassian.jira.user.util.UserUtilImpl.getActiveUserCount(UserUtilImpl.java:672)
	at com.atlassian.jira.issue.search.searchers.util.UserSearcherHelperImpl.getSuggestedUsers(UserSearcherHelperImpl.java:135)
	at com.atlassian.jira.issue.search.searchers.util.UserSearcherHelperImpl.addUserGroupSuggestionParams(UserSearcherHelperImpl.java:66)
	at com.atlassian.jira.issue.search.searchers.renderer.AbstractUserSearchRenderer.getKickassVelocityParams(AbstractUserSearchRenderer.java:226)
	at com.atlassian.jira.issue.search.searchers.renderer.AbstractUserSearchRenderer.getVelocityParams(AbstractUserSearchRenderer.java:202)
	at com.atlassian.jira.issue.search.searchers.renderer.AbstractUserSearchRenderer.getEditHtml(AbstractUserSearchRenderer.java:92)
	at com.atlassian.jira.plugin.issuenav.service.DefaultSearcherService.getEditHtml(DefaultSearcherService.java:467)
	at com.atlassian.jira.plugin.issuenav.service.DefaultSearcherService.getValueResults(DefaultSearcherService.java:258)
	at com.atlassian.jira.plugin.issuenav.service.DefaultSearcherService.getSearchResults(DefaultSearcherService.java:178)
	at com.atlassian.jira.plugin.issuenav.service.DefaultSearcherService.searchWithJql(DefaultSearcherService.java:172)
	at com.atlassian.jira.plugin.issuenav.action.SearchAction.doJql(SearchAction.java:61)
	at sun.reflect.GeneratedMethodAccessor1645.invoke(Unknown Source)
...