Report "Script Execution Time" as the time spent executing the script in the last 30 seconds. Use a sliding window to calculate this.

Notes:
- This metric provides a better indication of which scripts are taking up a lot of CPU (and therefore should be optimized).
- Previously the execution time was reset to 0 in every new measurement period, causing the reported time to fluctuate for no reason. This has been fixed by using a sliding window.
0.8.2-post-fixes
Oren Hurvitz 2015-07-27 12:16:21 +03:00
parent 287096d826
commit a3bed1fbcb
4 changed files with 241 additions and 51 deletions

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@ -0,0 +1,223 @@
using System;
using System.Diagnostics;
namespace OpenSim.Framework
{
/// <summary>
/// A MetricsCollector for 'long' values.
/// </summary>
public class MetricsCollectorLong : MetricsCollector<long>
{
public MetricsCollectorLong(int windowSize, int numBuckets)
: base(windowSize, numBuckets)
{
}
protected override long GetZero() { return 0; }
protected override long Add(long a, long b) { return a + b; }
}
/// <summary>
/// A MetricsCollector for time spans.
/// </summary>
public class MetricsCollectorTime : MetricsCollectorLong
{
public MetricsCollectorTime(int windowSize, int numBuckets)
: base(windowSize, numBuckets)
{
}
public void AddSample(Stopwatch timer)
{
long ticks = timer.ElapsedTicks;
if (ticks > 0)
AddSample(ticks);
}
public TimeSpan GetSumTime()
{
return TimeSpan.FromMilliseconds((GetSum() * 1000) / Stopwatch.Frequency);
}
}
struct MetricsBucket<T>
{
public T value;
public int count;
}
/// <summary>
/// Collects metrics in a sliding window.
/// </summary>
/// <remarks>
/// MetricsCollector provides the current Sum of the metrics that it collects. It can easily be extended
/// to provide the Average, too. It uses a sliding window to keep these values current.
///
/// This class is not thread-safe.
///
/// Subclass MetricsCollector to have it use a concrete value type. Override the abstract methods.
/// </remarks>
public abstract class MetricsCollector<T>
{
private int bucketSize; // e.g. 3,000 ms
private MetricsBucket<T>[] buckets;
private int NumBuckets { get { return buckets.Length; } }
// The number of the current bucket, if we had an infinite number of buckets and didn't have to wrap around
long curBucketGlobal;
// The total of all the buckets
T totalSum;
int totalCount;
/// <summary>
/// Returns the default (zero) value.
/// </summary>
/// <returns></returns>
protected abstract T GetZero();
/// <summary>
/// Adds two values.
/// </summary>
protected abstract T Add(T a, T b);
/// <summary>
/// Creates a MetricsCollector.
/// </summary>
/// <param name="windowSize">The period of time over which to collect the metrics, in ms. E.g.: 30,000.</param>
/// <param name="numBuckets">The number of buckets to divide the samples into. E.g.: 10. Using more buckets
/// smooths the jarring that occurs whenever we drop an old bucket, but uses more memory.</param>
public MetricsCollector(int windowSize, int numBuckets)
{
bucketSize = windowSize / numBuckets;
buckets = new MetricsBucket<T>[numBuckets];
Reset();
}
public void Reset()
{
ZeroBuckets(0, NumBuckets);
curBucketGlobal = GetNow() / bucketSize;
totalSum = GetZero();
totalCount = 0;
}
public void AddSample(T sample)
{
MoveWindow();
int curBucket = (int)(curBucketGlobal % NumBuckets);
buckets[curBucket].value = Add(buckets[curBucket].value, sample);
buckets[curBucket].count++;
totalSum = Add(totalSum, sample);
totalCount++;
}
/// <summary>
/// Returns the total values in the collection window.
/// </summary>
public T GetSum()
{
// It might have been a while since we last added a sample, so we may need to adjust the window
MoveWindow();
return totalSum;
}
/// <summary>
/// Returns the current time in ms.
/// </summary>
private long GetNow()
{
return DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
}
/// <summary>
/// Clears the values in buckets [offset, offset+num)
/// </summary>
private void ZeroBuckets(int offset, int num)
{
for (int i = 0; i < num; i++)
{
buckets[offset + i].value = GetZero();
buckets[offset + i].count = 0;
}
}
/// <summary>
/// Adjusts the buckets so that the "current bucket" corresponds to the current time.
/// This may require dropping old buckets.
/// </summary>
/// <remarks>
/// This method allows for the possibility that we don't get new samples for each bucket, so the
/// new bucket may be some distance away from the last used bucket.
/// </remarks>
private void MoveWindow()
{
long newBucketGlobal = GetNow() / bucketSize;
long bucketsDistance = newBucketGlobal - curBucketGlobal;
if (bucketsDistance == 0)
{
// We're still on the same bucket as before
return;
}
if (bucketsDistance >= NumBuckets)
{
// Discard everything
Reset();
return;
}
int curBucket = (int)(curBucketGlobal % NumBuckets);
int newBucket = (int)(newBucketGlobal % NumBuckets);
// Clear all the buckets in this range: (cur, new]
int numToClear = (int)bucketsDistance;
if (curBucket < NumBuckets - 1)
{
// Clear buckets at the end of the window
int num = Math.Min((int)bucketsDistance, NumBuckets - (curBucket + 1));
ZeroBuckets(curBucket + 1, num);
numToClear -= num;
}
if (numToClear > 0)
{
// Clear buckets at the beginning of the window
ZeroBuckets(0, numToClear);
}
// Move the "current bucket" pointer
curBucketGlobal = newBucketGlobal;
RecalcTotal();
}
private void RecalcTotal()
{
totalSum = GetZero();
totalCount = 0;
for (int i = 0; i < NumBuckets; i++)
{
totalSum = Add(totalSum, buckets[i].value);
totalCount += buckets[i].count;
}
}
}
}

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@ -109,14 +109,9 @@ namespace OpenSim.Region.ScriptEngine.Interfaces
DateTime TimeStarted { get; }
/// <summary>
/// Tick the last measurement period was started.
/// Collects information about how long the script was executed.
/// </summary>
long MeasurementPeriodTickStart { get; }
/// <summary>
/// Ticks spent executing in the last measurement period.
/// </summary>
long MeasurementPeriodExecutionTime { get; }
MetricsCollectorTime ExecutionTime { get; }
/// <summary>
/// Scene part in which this script instance is contained.

View File

@ -199,11 +199,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
public DateTime TimeStarted { get; private set; }
public long MeasurementPeriodTickStart { get; private set; }
public MetricsCollectorTime ExecutionTime { get; private set; }
public long MeasurementPeriodExecutionTime { get; private set; }
public static readonly int MaxMeasurementPeriod = 30 * 1000; // show the *recent* time used by the script, to find currently active scripts
private static readonly int MeasurementWindow = 30 * 1000; // show the *recent* time used by the script, to find currently active scripts
private bool m_coopTermination;
@ -246,6 +244,8 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
m_SaveState = StatePersistedHere;
ExecutionTime = new MetricsCollectorTime(MeasurementWindow, 10);
// m_log.DebugFormat(
// "[SCRIPT INSTANCE]: Instantiated script instance {0} (id {1}) in part {2} (id {3}) in object {4} attached avatar {5} in {6}",
// ScriptTask.Name, ScriptTask.ItemID, Part.Name, Part.UUID, Part.ParentGroup.Name, m_AttachedAvatar, Engine.World.Name);
@ -505,8 +505,10 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
Running = true;
TimeStarted = DateTime.Now;
MeasurementPeriodTickStart = Util.EnvironmentTickCount();
MeasurementPeriodExecutionTime = 0;
// Note: we don't reset ExecutionTime. The reason is that runaway scripts are stopped and restarted
// automatically, and we *do* want to show that they had high CPU in that case. If we had reset
// ExecutionTime here then runaway scripts, paradoxically, would never show up in the "Top Scripts" dialog.
if (EventQueue.Count > 0)
{
@ -832,20 +834,13 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
m_EventStart = DateTime.Now;
m_InEvent = true;
// Reset the measurement period when we reach the end of the current one.
if (Util.EnvironmentTickCountSubtract((int)MeasurementPeriodTickStart) > MaxMeasurementPeriod)
{
MeasurementPeriodTickStart = Util.EnvironmentTickCount();
MeasurementPeriodExecutionTime = 0;
}
Stopwatch executionTime = new Stopwatch();
executionTime.Start();
Stopwatch timer = new Stopwatch();
timer.Start();
m_Script.ExecuteEvent(State, data.EventName, data.Params);
executionTime.Stop();
MeasurementPeriodExecutionTime += executionTime.ElapsedMilliseconds;
timer.Stop();
ExecutionTime.AddSample(timer);
m_InEvent = false;
m_CurrentEvent = String.Empty;

View File

@ -2343,7 +2343,6 @@ namespace OpenSim.Region.ScriptEngine.XEngine
public Dictionary<uint, float> GetObjectScriptsExecutionTimes()
{
long tickNow = Util.EnvironmentTickCount();
Dictionary<uint, float> topScripts = new Dictionary<uint, float>();
lock (m_Scripts)
@ -2353,7 +2352,7 @@ namespace OpenSim.Region.ScriptEngine.XEngine
if (!topScripts.ContainsKey(si.LocalID))
topScripts[si.RootLocalID] = 0;
topScripts[si.RootLocalID] += CalculateAdjustedExectionTime(si, tickNow);
topScripts[si.RootLocalID] += GetExectionTime(si);
}
}
@ -2367,7 +2366,6 @@ namespace OpenSim.Region.ScriptEngine.XEngine
return 0.0f;
}
float time = 0.0f;
long tickNow = Util.EnvironmentTickCount();
IScriptInstance si;
// Calculate the time for all scripts that this engine is executing
// Ignore any others
@ -2376,36 +2374,15 @@ namespace OpenSim.Region.ScriptEngine.XEngine
si = GetInstance(id);
if (si != null && si.Running)
{
time += CalculateAdjustedExectionTime(si, tickNow);
time += GetExectionTime(si);
}
}
return time;
}
private float CalculateAdjustedExectionTime(IScriptInstance si, long tickNow)
private float GetExectionTime(IScriptInstance si)
{
long ticksElapsed = Util.EnvironmentTickCountSubtract((int)tickNow, (int)si.MeasurementPeriodTickStart);
// Avoid divide by zero
if (ticksElapsed == 0)
ticksElapsed = 1;
// Scale execution time to the ideal 55 fps frame time for these reasons.
//
// 1) XEngine does not execute scripts per frame, unlike other script engines. Hence, there is no
// 'script execution time per frame', which is the original purpose of this value.
//
// 2) Giving the raw execution times is misleading since scripts start at different times, making
// it impossible to compare scripts.
//
// 3) Scaling the raw execution time to the time that the script has been running is better but
// is still misleading since a script that has just been rezzed may appear to have been running
// for much longer.
//
// 4) Hence, we scale execution time to an idealised frame time (55 fps). This is also not perfect
// since the figure does not represent actual execution time and very hard running scripts will
// never exceed 18ms (though this is a very high number for script execution so is a warning sign).
return ((float)si.MeasurementPeriodExecutionTime / ticksElapsed) * 18.1818f;
return (float)si.ExecutionTime.GetSumTime().TotalMilliseconds;
}
public void SuspendScript(UUID itemID)