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copied!<p>Here are the results of my own speed testing (finally).</p> <p>In my tests I used the following code. I used 1 million iterations to keep wait times down. -1 to 13 is to give some out of bounds work. When array setup is required, it was included in the total time, but only done once. Each function got its own calling procedure with the name (X) hardcoded:</p> <pre><code>Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabel_X(j, False, False) str = ComputeLabel_X(j, True, False) str = ComputeLabel_X(j, False, True) Next Next </code></pre> <p>I also got different results when running the code with F5 (break into code on error) and Ctrl-F5 (run outside of debugger). I guess the second one has more validity for the SSRS code environment as nothing would be attaching to the process to debug it. </p> <p>All results are compile without debug (Ctrl-F5).</p> <ul> <li>Russ: 613 ms (bounds checking added)</li> <li>Erik: 614 ms (same as Russ but arrays populated as array literal {} instead of individual statements)</li> <li>Erik2: 526 ms (0 to 12, with an extra 0 to 2, no bounds checking)</li> <li>Steve: 660 ms</li> <li>Steve2: 873 ms (remove ElseIf for individual If statements)</li> <li>New: 2977 ms (The first idea from my previous answer)</li> <li>Initial Post: 3915 ms * - revised to be correct (was 10 times too small)</li> <li>Original: 3947 ms (the version you've never seen, the one I optimized to post here)</li> <li>Choose: 11068 ms</li> <li>BigArray: 12565 ms (calculating the index into a big array with math)</li> </ul> <p>Even though execution times could fluctuate by as much as 100 ms for the higher values, the rankings tended to stay consistent, except for the Russ and Erik versions which kept swapping.</p> <p>Takeaways:</p> <ul> <li><p>Building the array once is insignificant. Doing it as individual statements or as an array literal {} is identical.</p></li> <li><p>It cost 20% more to do bounds checking for the array method.</p></li> <li><p>Expanding the entire thing intuitively seems like it should be fastest, but it isn't. I don't know why. Perhaps it has something to do with processor cache line size and preloading tradeoffs, or something like that.</p></li> <li><p>The only real changes I made from the original function to the function I posted in my question were: 1) Return from each case statement instead of assign the string to a variable and return that at the end (plus removing the variable), 2) swap the independent If Flag statements order and change the second If to an ElseIf. The 1% improvement was insignificant</p></li> <li><p><strike>It seems like I should be able to generalize something from the fact that my version listed as "New" (the first query in the other answer I posted) did so badly. Is it the longer strings? Is it that Returning is equally fast no matter where in the procedure it's done, but falling out of the Case statement to execute more instructions is slow?</strike></p></li> <li><p>Russ's array version is fastest. An array lookup is faster than a case statement with string concatenation.</p></li> <li><p>At this point I am not sure how to explain why the New version is faster.</p></li> <li><p>The Choose function is super, super slow.</p></li> </ul> <p><strike>Because of these tests I have to award the answer for this question to nobugz who claimed that I couldn't optimize the given code. So far, he's been right!</strike></p> <p>Update: I am really sorry about the mistake I made that left off a zero on the number of iterations testing the Initial Post version. Things have been corrected now.</p> <p>Addendum: The (corrected) testing code:</p> <pre><code>Module Module1 Dim _Labels(12) As String Dim _ConditionalLabels(12) As String Dim _HeldLabels(12) As String Dim Labels() As String Dim ConditionalLabels() As String Dim HeldLabels() As String Dim OrderLabelsBigArray(38) As String Sub Main() Dim sw As New Stopwatch() sw.Start() ComputeLabelsFirstPosted() sw.Stop() Console.WriteLine("FirstPosted " & sw.ElapsedMilliseconds & " ms") sw.Reset() sw.Start() ComputeLabelsRuss() sw.Stop() Console.WriteLine("Russ " & sw.ElapsedMilliseconds & " ms") sw.Reset() sw.Start() ComputeLabelsErik() sw.Stop() Console.WriteLine("Erik " & sw.ElapsedMilliseconds & " ms") sw.Reset() sw.Start() ComputeLabelsErik2() sw.Stop() Console.WriteLine("Erik2 " & sw.ElapsedMilliseconds & " ms") sw.Reset() sw.Start() ComputeLabelsBigArray() sw.Stop() Console.WriteLine("BigArray " & sw.ElapsedMilliseconds & " ms") sw.Reset() sw.Start() ComputeLabelsSteve() sw.Stop() Console.WriteLine("Steve " & sw.ElapsedMilliseconds & " ms") sw.Reset() sw.Start() ComputeLabelsSteve2() sw.Stop() Console.WriteLine("Steve2 " & sw.ElapsedMilliseconds & " ms") sw.Reset() sw.Start() ComputeLabelsNew() sw.Stop() Console.WriteLine("New " & sw.ElapsedMilliseconds & " ms") sw.Reset() sw.Start() ComputeLabelsChoose() sw.Stop() Console.WriteLine("Choose " & sw.ElapsedMilliseconds & " ms") sw.Reset() sw.Start() ComputeLabelsOriginal() sw.Stop() Console.WriteLine("Original " & sw.ElapsedMilliseconds & " ms") Console.Read() End Sub Public Sub ComputeLabelsFirstPosted() Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabelFirstPosted(j, False, False) str = ComputeLabelFirstPosted(j, True, False) str = ComputeLabelFirstPosted(j, False, True) Next Next End Sub Public Function ComputeLabelFirstPosted(ByVal Action As Integer, ByVal IsHeld As Boolean, ByVal IsConditional As Boolean) As String Dim Prefix As String = "" If IsConditional Then Prefix = "Conditional " ElseIf IsHeld Then Prefix = "Held " End If Select Case Action Case 0 Return "" Case 1 Return Prefix & "Cancelled" Case 2 Return Prefix & "Discontinued" Case 3 Return Prefix & "Suspended" Case 4 Return Prefix & "Unsuspended" Case 6 Return Prefix & "Collected" Case 7 Return Prefix & "Released from Hold" Case 8 Return Prefix & "Modified" Case 9 Return Prefix & "Discontinued for the Future" Case 10 Return Prefix & "Verified" Case 11 Return Prefix & "Modified And Verified" Case 12 Return "Hold " & Prefix & "Cancelled" Case Else Return "" End Select End Function Sub ComputeLabelsRuss() _Labels(0) = "" _Labels(1) = "Cancelled" _Labels(2) = "Discontinued" _Labels(3) = "Suspended" _Labels(4) = "Unsuspended" _Labels(6) = "Collected" _Labels(7) = "Released from Hold" _Labels(8) = "Modified" _Labels(9) = "Discontinued for the Future" _Labels(10) = "Verified" _Labels(11) = "Modified And Verified" _Labels(12) = "Hold Cancelled" _ConditionalLabels(0) = "" _ConditionalLabels(1) = "Conditional Cancelled" _ConditionalLabels(2) = "Conditional Discontinued" _ConditionalLabels(3) = "Conditional Suspended" _ConditionalLabels(4) = "Conditional Unsuspended" _ConditionalLabels(6) = "Conditional Collected" _ConditionalLabels(7) = "Conditional Released from Hold" _ConditionalLabels(8) = "Conditional Modified" _ConditionalLabels(9) = "Conditional Discontinued for the Future" _ConditionalLabels(10) = "Conditional Verified" _ConditionalLabels(11) = "Conditional Modified And Verified" _ConditionalLabels(12) = "Hold Conditional Cancelled" _HeldLabels(0) = "" _HeldLabels(1) = "Held Cancelled" _HeldLabels(2) = "Held Discontinued" _HeldLabels(3) = "Held Suspended" _HeldLabels(4) = "Held Unsuspended" _HeldLabels(6) = "Held Collected" _HeldLabels(7) = "Held Released from Hold" _HeldLabels(8) = "Held Modified" _HeldLabels(9) = "Held Discontinued for the Future" _HeldLabels(10) = "Held Verified" _HeldLabels(11) = "Held Modified And Verified" _HeldLabels(12) = "Hold Held Cancelled" Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabelRuss(j, False, False) str = ComputeLabelRuss(j, True, False) str = ComputeLabelRuss(j, False, True) Next Next End Sub Public Function ComputeLabelRuss(ByVal Action As Integer, ByVal Held As Boolean, ByVal Conditional As Boolean) As String If Action < 0 OrElse Action > 12 Then Return "" If Conditional Then Return _ConditionalLabels(Action) If Held Then Return _HeldLabels(Action) Return _Labels(Action) End Function Public Sub ComputeLabelsNew() Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabelNew(j, False, False) str = ComputeLabelNew(j, True, False) str = ComputeLabelNew(j, False, True) Next Next End Sub Public Function ComputeLabelNew(ByVal Action As Integer, ByVal IsHeld As Boolean, ByVal IsConditional As Boolean) As String Dim Status As String = "" Select Case Action Case 0 Return "" Case 1 Status = "Cancelled" Case 2 Status = "Discontinued" Case 3 Status = "Suspended" Case 4 Status = "Unsuspended" Case 6 Status = "Collected" Case 7 Status = "Released from Hold" Case 8 Status = "Modified" Case 9 Status = "Discontinued for the Future" Case 10 Status = "Verified" Case 11 Status = "Modified And Verified" Case 12 If IsConditional Then Return "Hold Conditional Cancelled" If IsHeld Then Return "Hold Held Cancelled" Return "Hold Cancelled" Case Else Return "" End Select If IsConditional Then Return "Conditional " & Status If IsHeld Then Return "Held " & Status Return Status End Function Sub ComputeLabelsErik() Labels = New String() {"", "Cancelled", "Discontinued", "Suspended", "Unsuspended", "", "Collected", "Released from Hold", "Modified", "Discontinued for the Future", "Verified", "Modified And Verified", "Hold Cancelled"} ConditionalLabels = New String() {"", "Conditional Cancelled", "Conditional Discontinued", "Conditional Suspended", "Conditional Unsuspended", "Conditional ", "Conditional Collected", "Conditional Released from Hold", "Conditional Modified", "Conditional Discontinued for the Future", "Conditional Verified", "Conditional Modified And Verified", "Hold Cancelled"} HeldLabels = New String() {"", "Held Cancelled", "Held Discontinued", "Held Suspended", "Held Unsuspended", "Held ", "Held Collected", "Held Released from Hold", "Held Modified", "Held Discontinued for the Future", "Held Verified", "Held Modified And Verified", "Hold Cancelled"} Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabelErik(j, False, False) str = ComputeLabelErik(j, True, False) str = ComputeLabelErik(j, False, True) Next Next End Sub Public Function ComputeLabelErik(ByVal Action As Integer, ByVal Held As Boolean, ByVal Conditional As Boolean) As String If Action < 0 OrElse Action > 12 Then Return "" If Conditional Then Return ConditionalLabels(Action) If Held Then Return HeldLabels(Action) Return Labels(Action) End Function Sub ComputeLabelsErik2() Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = 0 To 12 str = ComputeLabelErik2(j, False, False) str = ComputeLabelErik2(j, True, False) str = ComputeLabelErik2(j, False, True) Next For j As Integer = 1 To 2 str = ComputeLabelErik2(j, False, False) str = ComputeLabelErik2(j, True, False) str = ComputeLabelErik2(j, False, True) Next Next End Sub Public Function ComputeLabelErik2(ByVal Action As Integer, ByVal Held As Boolean, ByVal Conditional As Boolean) As String If Conditional Then Return ConditionalLabels(Action) If Held Then Return HeldLabels(Action) Return Labels(Action) End Function Public Sub ComputeLabelsOriginal() Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabelOriginal(j, False, False) str = ComputeLabelOriginal(j, True, False) str = ComputeLabelOriginal(j, False, True) Next Next End Sub Public Function ComputeLabelOriginal(ByVal Action As Integer, ByVal bIsHeld As Boolean, _ ByVal bIsConditional As Boolean) As String Dim strReprintLabel As String = "" Dim strOrderActionPrefix As String = "" If (bIsHeld) Then strOrderActionPrefix = "Held " End If If (bIsConditional) Then strOrderActionPrefix = "Conditional " End If Select Case Action Case 0 ' Normal Order strReprintLabel = "" Case 1 strReprintLabel = strOrderActionPrefix & "Order Cancelled" Case 2 strReprintLabel = strOrderActionPrefix & "Order Discontinued" Case 3 strReprintLabel = strOrderActionPrefix & "Order Suspended" Case 4 strReprintLabel = strOrderActionPrefix & "Order Unsuspended" Case 6 strReprintLabel = strOrderActionPrefix & "Order Collected" Case 7 strReprintLabel = strOrderActionPrefix & "Order Released from Hold" Case 8 strReprintLabel = strOrderActionPrefix & "Order Modified" Case 9 strReprintLabel = strOrderActionPrefix & "Order Discontinued for the Future" Case 10 strReprintLabel = strOrderActionPrefix & "Order Verified" Case 11 strReprintLabel = strOrderActionPrefix & "Order Modified And Verified" Case 12 strReprintLabel = "Hold " & strOrderActionPrefix & "Order Cancelled" Case Else strReprintLabel = "" End Select Return strReprintLabel End Function Sub ComputeLabelsSteve2() Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabelSteve2(j, False, False) str = ComputeLabelSteve2(j, True, False) str = ComputeLabelSteve2(j, False, True) Next Next End Sub Public Function ComputeLabelSteve2(ByVal Action As Integer, ByVal IsHeld As Boolean, ByVal IsConditional As Boolean) As String Select Case Action Case 0 Return "" Case 1 If IsConditional Then Return "Conditional Cancelled" If IsHeld Then Return "Held Cancelled" Return "Cancelled" Case 2 If IsConditional Then Return "Conditional Discontinued" If IsHeld Then Return "Held Discontinued" Return "Discontinued" Case 3 If IsConditional Then Return "Conditional Suspended" If IsHeld Then Return "Held Suspended" Return "Suspended" Case 4 If IsConditional Then Return "Conditional Unsuspended" If IsHeld Then Return "Held Unsuspended" Return "Unsuspended" Case 6 If IsConditional Then Return "Conditional Collected" If IsHeld Then Return "Held Collected" Return "Collected" Case 7 If IsConditional Then Return "Conditional Released from Hold" If IsHeld Then Return "Held Released from Hold" Return "Released from Hold" Case 8 If IsConditional Then Return "Conditional Modified" If IsHeld Then Return "Held Modified" Return "Modified" Case 9 If IsConditional Then Return "Conditional Discontinued for the Future" If IsHeld Then Return "Held Discontinued for the Future" Return "Discontinued for the Future" Case 10 If IsConditional Then Return "Conditional Verified" If IsHeld Then Return "Held Verified" Return "Verified" Case 11 If IsConditional Then Return "Conditional Modified And Verified" If IsHeld Then Return "Held Modified And Verified" Return "Modified And Verified" Case 12 If IsConditional Then Return "Hold Conditional Cancelled" If IsHeld Then Return "Hold Held Cancelled" Return "Hold Cancelled" Case Else Return "" End Select End Function Sub ComputeLabelsSteve() Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabelSteve(j, False, False) str = ComputeLabelSteve(j, True, False) str = ComputeLabelSteve(j, False, True) Next Next End Sub Public Function ComputeLabelSteve(ByVal Action As Integer, ByVal IsHeld As Boolean, ByVal IsConditional As Boolean) As String Select Case Action Case 0 Return "" Case 1 If IsConditional Then Return "Conditional Cancelled" ElseIf IsHeld Then Return "Held Cancelled" Else Return "Cancelled" End If Case 2 If IsConditional Then Return "Conditional Discontinued" ElseIf IsHeld Then Return "Held Discontinued" Else Return "Discontinued" End If Case 3 If IsConditional Then Return "Conditional Suspended" ElseIf IsHeld Then Return "Held Suspended" Else Return "Suspended" End If Case 4 If IsConditional Then Return "Conditional Unsuspended" ElseIf IsHeld Then Return "Held Unsuspended" Else Return "Unsuspended" End If Case 6 If IsConditional Then Return "Conditional Collected" ElseIf IsHeld Then Return "Held Collected" Else Return "Collected" End If Case 7 If IsConditional Then Return "Conditional Released from Hold" ElseIf IsHeld Then Return "Held Released from Hold" Else Return "Released from Hold" End If Case 8 If IsConditional Then Return "Conditional Modified" ElseIf IsHeld Then Return "Held Modified" Else Return "Modified" End If Case 9 If IsConditional Then Return "Conditional Discontinued for the Future" ElseIf IsHeld Then Return "Held Discontinued for the Future" Else Return "Discontinued for the Future" End If Case 10 If IsConditional Then Return "Conditional Verified" ElseIf IsHeld Then Return "Held Verified" Else Return "Verified" End If Case 11 If IsConditional Then Return "Conditional Modified And Verified" ElseIf IsHeld Then Return "Held Modified And Verified" Else Return "Modified And Verified" End If Case 12 If IsConditional Then Return "Hold Conditional Cancelled" ElseIf IsHeld Then Return "Hold Held Cancelled" Else Return "Hold Cancelled" End If Case Else Return "" End Select End Function Sub ComputeLabelsChoose() Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabelChoose(j, False, False) str = ComputeLabelChoose(j, True, False) str = ComputeLabelChoose(j, False, True) Next Next End Sub Public Function ComputeLabelChoose(ByVal Action As Integer, ByVal IsHeld As Boolean, ByVal IsConditional As Boolean) As String Dim Status As String = "" Select Case Action Case 0, 5 Return "" Case 1 To 11 Status = Choose(Action, "Cancelled", "Discontinued", "Suspended", _ "Unsuspended", "Collected", "Released from Hold", "Modified", _ "Discontinued for the Future", "Verified", "Modified And Verified") Case 12 If IsConditional Then Return "Hold Conditional Cancelled" ElseIf IsHeld Then Return "Hold Held Cancelled" Else Return "Hold Cancelled" End If Case Else Return "" End Select If IsConditional Then Return "Conditional " & Status If IsHeld Then Return "Held " & Status Return Status End Function Sub ComputeLabelsBigArray() OrderLabelsBigArray = New String() {"", "Cancelled", "Discontinued", "Suspended", "Unsuspended", "", "Collected", "Released from Hold", "Modified", "Discontinued for the Future", "Verified", "Modified And Verified", "Hold Cancelled", _ "", "Conditional Cancelled", "Conditional Discontinued", "Conditional Suspended", "Conditional Unsuspended", "Conditional ", "Conditional Collected", "Conditional Released from Hold", "Conditional Modified", "Conditional Discontinued for the Future", "Conditional Verified", "Conditional Modified And Verified", "Hold Cancelled", _ "", "Held Cancelled", "Held Discontinued", "Held Suspended", "Held Unsuspended", "Held ", "Held Collected", "Held Released from Hold", "Held Modified", "Held Discontinued for the Future", "Held Verified", "Held Modified And Verified", "Hold Cancelled"} Dim str As String = "" For i As Integer = 0 To 1000000 For j As Integer = -1 To 13 str = ComputeLabelChoose(j, False, False) str = ComputeLabelChoose(j, True, False) str = ComputeLabelChoose(j, False, True) Next Next End Sub Public Function ComputeLabelBigArray(ByVal Action As Integer, ByVal IsHeld As Boolean, ByVal IsConditional As Boolean) As String If Action < 0 OrElse Action >= 13 Then Return "" Return OrderLabelsBigArray(Action - IsConditional * 13 - (IsHeld AndAlso Not IsConditional) * 26) End Function End Module </code></pre> <p>Now if I made another mistake, someone can help find it.</p>

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