diff --git a/src/TfsAdvanced.DataStore/Repository/BuildRepository.cs b/src/TfsAdvanced.DataStore/Repository/BuildRepository.cs
index e866097..fe72f4b 100644
--- a/src/TfsAdvanced.DataStore/Repository/BuildRepository.cs
+++ b/src/TfsAdvanced.DataStore/Repository/BuildRepository.cs
@@ -38,7 +38,7 @@ public override bool Update(IEnumerable<Build> updates)
         {
             var updated = base.Update(updates);
             DateTime yesterday = DateTime.Now.Date.AddDays(-2);
-            base.Cleanup(x => x.QueuedDate < yesterday);
+            base.CleanupIfNeeded(x => x.QueuedDate < yesterday);
             return updated;
         }
     }
diff --git a/src/TfsAdvanced.DataStore/Repository/JobRequestRepository.cs b/src/TfsAdvanced.DataStore/Repository/JobRequestRepository.cs
index 1015001..8dbe2a2 100644
--- a/src/TfsAdvanced.DataStore/Repository/JobRequestRepository.cs
+++ b/src/TfsAdvanced.DataStore/Repository/JobRequestRepository.cs
@@ -23,7 +23,7 @@ public override bool Update(IEnumerable<QueueJob> updates)
         {
             var updated = base.Update(updates);
             DateTime yesterday = DateTime.Now.Date.AddDays(-2);
-            base.Cleanup(x => x.QueuedTime < yesterday);
+            base.CleanupIfNeeded(x => x.QueuedTime < yesterday);
             return updated;
         }
 
diff --git a/src/TfsAdvanced.DataStore/Repository/PullRequestRepository.cs b/src/TfsAdvanced.DataStore/Repository/PullRequestRepository.cs
index 573730a..4b77ee6 100644
--- a/src/TfsAdvanced.DataStore/Repository/PullRequestRepository.cs
+++ b/src/TfsAdvanced.DataStore/Repository/PullRequestRepository.cs
@@ -27,7 +27,7 @@ public override bool Update(IEnumerable<PullRequest> updates)
             var noUpdate = base.GetList(request => !updates.Select(x => x.Id).Contains(request.Id));
             bool removed = base.Remove(noUpdate);
             DateTime yesterday = DateTime.Now.Date.AddDays(-2);
-            base.Cleanup(request => request.ClosedDate.HasValue && request.ClosedDate < yesterday );
+            base.CleanupIfNeeded(request => request.ClosedDate.HasValue && request.ClosedDate < yesterday );
             return updated || removed;
 
         }
diff --git a/src/TfsAdvanced.DataStore/Repository/RepositoryBase.cs b/src/TfsAdvanced.DataStore/Repository/RepositoryBase.cs
index 77ac62d..6efa487 100644
--- a/src/TfsAdvanced.DataStore/Repository/RepositoryBase.cs
+++ b/src/TfsAdvanced.DataStore/Repository/RepositoryBase.cs
@@ -12,12 +12,15 @@ public abstract class RepositoryBase<T> : IRepository<T>
         protected readonly Dictionary<int, T> data;
         protected readonly Mutex mutex;
         protected DateTime LastUpdated;
+        protected DateTime LastCleanup;
+        
 
         protected RepositoryBase()
         {
             this.data = new Dictionary<int, T>();
             this.mutex = new Mutex();
             this.LastUpdated = DateTime.Now;
+            this.LastCleanup = DateTime.Now;
         }
 
         protected abstract int GetId(T item);
@@ -162,7 +165,16 @@ public DateTime GetLastUpdated()
             return DateTime.MinValue;
         }
 
-        protected void Cleanup(Predicate<T> removePredicate)
+        protected void CleanupIfNeeded(Predicate<T> removePredicate)
+        {
+            // Only run cleanup every 3 hours
+            if (LastUpdated.AddHours(3) > DateTime.Now)
+            {
+                Cleanup(removePredicate);
+            }
+        }
+
+        private void Cleanup(Predicate<T> removePredicate)
         {
             if (mutex.WaitOne(60))
             {
@@ -174,6 +186,7 @@ protected void Cleanup(Predicate<T> removePredicate)
                         var key = GetId(item);
                         data.Remove(key);
                     }
+                    LastCleanup = DateTime.Now;
                 }
                 finally
                 {
diff --git a/src/TfsAdvanced.Models/Infrastructure/AppSettings.cs b/src/TfsAdvanced.Models/Infrastructure/AppSettings.cs
index 7ba2ccb..e91f027 100644
--- a/src/TfsAdvanced.Models/Infrastructure/AppSettings.cs
+++ b/src/TfsAdvanced.Models/Infrastructure/AppSettings.cs
@@ -14,6 +14,6 @@ public class AppSettings
 
         public AuthorizationSettings authorization { get; set; }
 
-        public static int MAX_DEGREE_OF_PARALLELISM = -1;
+        public static int MAX_DEGREE_OF_PARALLELISM = 3;
     }
 }
\ No newline at end of file
diff --git a/src/TfsAdvanced/wwwroot/js/pullRequests.js b/src/TfsAdvanced/wwwroot/js/pullRequests.js
index 9395f9f..4582994 100644
--- a/src/TfsAdvanced/wwwroot/js/pullRequests.js
+++ b/src/TfsAdvanced/wwwroot/js/pullRequests.js
@@ -21,7 +21,9 @@ function fetchData() {
 
 function HandlMyPullRequests(myPullRequests) {
 
-    if (!myPullRequests || myPullRequests.length === 0) {
+    if (!myPullRequests)
+        return;
+    else if (myPullRequests.length === 0) {
         $("#myPullRequests").hide();
     } else {
         $("#myPullRequests").show();
@@ -33,7 +35,9 @@ function HandlMyPullRequests(myPullRequests) {
 
 function HandleTeamPullRequests(pullRequests) {
 
-    if (!pullRequests || pullRequests.length === 0) {
+    if(!pullRequests)
+        return;
+    if (pullRequests.length === 0) {
         $("#pullRequestHeader").hide();
         $("#pullRequests").hide();
         $("#NoPullRequests").show();
@@ -63,7 +67,13 @@ function sortByDate(pullRequests, reverse = false) {
 }
 
 function HandleMyCompletedPullRequests(pullRequests) {
-    
-    sortByDate(pullRequests, true);
-    $("#myCompletedPullRequestsTable").html($("#completedPullRequestTemplate").tmpl(pullRequests));
+    if(!pullRequests)
+        return;
+    else if (pullRequests.length === 0) {
+        $("#myCompletedPullRequestsTable").hide();
+    } else {
+        $("#myCompletedPullRequestsTable").show();
+        sortByDate(pullRequests, true);
+        $("#myCompletedPullRequestsTable").html($("#completedPullRequestTemplate").tmpl(pullRequests));
+    }
 }
\ No newline at end of file