/// <summary>
/// Creates a snapshot of the current state of the performance counter.
/// </summary>
/// <returns>Newly created snapshot.</returns>
public BackendPerformanceSnapshot Snapshot()
{
var snap = new BackendPerformanceSnapshot(this.insertedEntities, this.insertTime, this.queriedEntities, this.queryTime)
{
Start = this.Start,
// TODO: Would it not be better for these two guys to be part of the constructor? Either implicitly or explicitly.
Taken = this.dateTimeProvider.GetUtcNow()
};
return(snap);
}
public BackendPerformanceSnapshot Snapshot()
{
#if !(PORTABLE || NETCORE)
Thread.MemoryBarrier();
#endif
var snap = new BackendPerformanceSnapshot(this._InsertedEntities, this._InsertTime, this._QueriedEntities, this._QueryTime)
{
Start = this.Start,
Taken = DateTime.UtcNow
};
return(snap);
}
private void AddBenchStats(StringBuilder log)
{
log.AppendLine(">> Leveldb Bench");
BackendPerformanceSnapshot snapShot = this.performanceCounter.Snapshot();
if (this.latestPerformanceSnapShot == null)
{
log.AppendLine(snapShot.ToString());
}
else
{
log.AppendLine((snapShot - this.latestPerformanceSnapShot).ToString());
}
this.latestPerformanceSnapShot = snapShot;
}
private void AddBenchStats(StringBuilder log)
{
this.logger.LogTrace("()");
log.AppendLine("======DBreezeCoinView Bench======");
BackendPerformanceSnapshot snapShot = this.performanceCounter.Snapshot();
if (this.latestPerformanceSnapShot == null)
{
log.AppendLine(snapShot.ToString());
}
else
{
log.AppendLine((snapShot - this.latestPerformanceSnapShot).ToString());
}
this.latestPerformanceSnapShot = snapShot;
this.logger.LogTrace("(-)");
}
/// <summary>
/// Creates a snapshot based on difference of two performance counter snapshots.
/// <para>
/// This is used to obtain statistic information about performance of the backend
/// during certain period.</para>
/// </summary>
/// <param name="end">Newer performance counter snapshot.</param>
/// <param name="start">Older performance counter snapshot.</param>
/// <returns>Snapshot of the difference between the two performance counter snapshots.</returns>
/// <remarks>The two snapshots should be taken from a single performance counter.
/// Otherwise the start times of the snapshots will be different, which is not allowed.</remarks>
public static BackendPerformanceSnapshot operator -(BackendPerformanceSnapshot end, BackendPerformanceSnapshot start)
{
if (end.Start != start.Start)
{
throw new InvalidOperationException("Performance snapshot should be taken from the same point of time");
}
if (end.Taken < start.Taken)
{
throw new InvalidOperationException("The difference of snapshot can't be negative");
}
long insertedEntities = end.totalInsertedEntities - start.totalInsertedEntities;
long insertTime = end.totalInsertTime - start.totalInsertTime;
long queriedEntities = end.totalQueriedEntities - start.totalQueriedEntities;
long queryTime = end.totalQueryTime - start.totalQueryTime;
var snapshot = new BackendPerformanceSnapshot(insertedEntities, insertTime, queriedEntities, queryTime)
{
Start = start.Taken,
Taken = end.Taken
};
return(snapshot);
}
