Use SpinLock for Histogram updates

[utpilla]

Use SpinLock for Histogram updates

Stress Test Results (high contention) with Prometheus Exporter scraping interval = 10s

Multiple threads updating the same Histogram MetricPoint in parallel

C:\opentelemetry-dotnet\test\OpenTelemetry.Tests.Stress.Metrics>dotnet run --framework net6.0 --configuration Release
Running (concurrency = 8, prometheusEndpoint = http://localhost:9184/metrics/), press <Esc> to stop...
2022-08-05T01:16:52.4112443Z Loops: 608,880,817, Loops/Second: 5,245,688, CPU Cycles/Loop: 809, RunwayTime (Seconds): 120
2022-08-05T01:16:52.6155305Z Loops: 609,941,306, Loops/Second: 5,189,631, CPU Cycles/Loop: 771, RunwayTime (Seconds): 120
2022-08-05T01:16:52.8181754Z Loops: 610,999,272, Loops/Second: 5,234,378, CPU Cycles/Loop: 797, RunwayTime (Seconds): 120
2022-08-05T01:16:53.0246690Z Loops: 612,015,025, Loops/Second: 4,943,883, CPU Cycles/Loop: 757, RunwayTime (Seconds): 121
2022-08-05T01:16:53.2289088Z Loops: 613,059,613, Loops/Second: 5,122,985, CPU Cycles/Loop: 715, RunwayTime (Seconds): 121
2022-08-05T01:16:53.4429513Z Loops: 614,153,916, Loops/Second: 5,128,685, CPU Cycles/Loop: 785, RunwayTime (Seconds): 121
2022-08-05T01:16:53.6454101Z Loops: 615,189,648, Loops/Second: 5,128,836, CPU Cycles/Loop: 794, RunwayTime (Seconds): 121

Stress Test Results (low contention) with Prometheus Exporter scraping interval = 10s

Multiple threads updating random Histogram MetricPoints in parallel

C:\opentelemetry-dotnet\test\OpenTelemetry.Tests.Stress.Metrics>dotnet run --framework net6.0 --configuration Release
Running (concurrency = 8, prometheusEndpoint = http://localhost:9184/metrics/), press <Esc> to stop...
2022-08-05T01:11:04.2566381Z Loops: 2,304,159,048, Loops/Second: 18,347,248, CPU Cycles/Loop: 1,199, RunwayTime (Seconds): 123
2022-08-05T01:11:04.4657673Z Loops: 2,308,429,744, Loops/Second: 18,360,469, CPU Cycles/Loop: 1,169, RunwayTime (Seconds): 123
2022-08-05T01:11:04.6900137Z Loops: 2,312,599,088, Loops/Second: 18,632,700, CPU Cycles/Loop: 1,151, RunwayTime (Seconds): 123
2022-08-05T01:11:04.9063550Z Loops: 2,316,445,679, Loops/Second: 18,469,933, CPU Cycles/Loop: 1,149, RunwayTime (Seconds): 123
2022-08-05T01:11:05.1313989Z Loops: 2,320,606,516, Loops/Second: 18,258,368, CPU Cycles/Loop: 1,137, RunwayTime (Seconds): 124
2022-08-05T01:11:05.3684671Z Loops: 2,324,848,830, Loops/Second: 18,537,724, CPU Cycles/Loop: 1,152, RunwayTime (Seconds): 124
2022-08-05T01:11:05.6004662Z Loops: 2,329,282,597, Loops/Second: 19,176,912, CPU Cycles/Loop: 1,165, RunwayTime (Seconds): 124

Benchmark Results

// * Summary *

BenchmarkDotNet=v0.13.1, OS=Windows 10.0.22000
Intel Core i7-9700 CPU 3.00GHz, 1 CPU, 8 logical and 8 physical cores
.NET SDK=6.0.302
[Host] : .NET 6.0.7 (6.0.722.32202), X64 RyuJIT
DefaultJob : .NET 6.0.7 (6.0.722.32202), X64 RyuJIT

Method	BoundCount	Mean	Error	StdDev	Median
HistogramHotPath	10	99.71 ns	1.953 ns	2.325 ns	100.7 ns
HistogramWith1LabelHotPath	10	156.72 ns	3.127 ns	3.840 ns	157.2 ns
HistogramWith3LabelsHotPath	10	256.47 ns	5.065 ns	8.600 ns	257.4 ns
HistogramWith5LabelsHotPath	10	354.00 ns	7.002 ns	12.804 ns	356.7 ns
HistogramWith7LabelsHotPath	10	416.66 ns	8.325 ns	14.798 ns	419.3 ns
HistogramHotPath	20	102.69 ns	2.057 ns	2.112 ns	102.9 ns
HistogramWith1LabelHotPath	20	160.90 ns	3.242 ns	4.438 ns	160.5 ns
HistogramWith3LabelsHotPath	20	264.90 ns	5.252 ns	8.629 ns	266.4 ns
HistogramWith5LabelsHotPath	20	352.43 ns	7.052 ns	11.974 ns	356.5 ns
HistogramWith7LabelsHotPath	20	423.21 ns	8.465 ns	16.106 ns	430.2 ns
HistogramHotPath	50	116.43 ns	2.297 ns	2.905 ns	117.3 ns
HistogramWith1LabelHotPath	50	168.06 ns	3.324 ns	4.659 ns	168.7 ns
HistogramWith3LabelsHotPath	50	279.30 ns	5.545 ns	10.945 ns	282.4 ns
HistogramWith5LabelsHotPath	50	373.72 ns	7.441 ns	11.363 ns	374.3 ns
HistogramWith7LabelsHotPath	50	438.49 ns	8.742 ns	8.977 ns	441.1 ns
HistogramHotPath	100	132.19 ns	2.671 ns	3.076 ns	133.2 ns
HistogramWith1LabelHotPath	100	187.76 ns	3.621 ns	4.169 ns	188.3 ns
HistogramWith3LabelsHotPath	100	300.96 ns	6.044 ns	8.273 ns	304.9 ns
HistogramWith5LabelsHotPath	100	405.44 ns	7.943 ns	12.827 ns	408.4 ns
HistogramWith7LabelsHotPath	100	479.73 ns	8.904 ns	8.329 ns	481.0 ns

[codecov]

Codecov Report

Merging #3550 (baee221) into main (666a0c1) will increase coverage by 0.24%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #3550      +/-   ##
==========================================
+ Coverage   87.04%   87.28%   +0.24%     
==========================================
  Files         275      275              
  Lines        9959     9968       +9     
==========================================
+ Hits         8669     8701      +32     
+ Misses       1290     1267      -23     

Impacted Files	Coverage Δ
src/OpenTelemetry/Metrics/MetricPoint.cs	87.24% <100.00%> (+2.24%)	⬆️
...tation/OpenTelemetryProtocolExporterEventSource.cs	75.00% <0.00%> (-10.00%)	⬇️
...ZPages/Implementation/ZPagesExporterEventSource.cs	56.25% <0.00%> (-6.25%)	⬇️
src/OpenTelemetry/Metrics/HistogramBuckets.cs	96.15% <0.00%> (-3.85%)	⬇️
...metryProtocol/Implementation/ActivityExtensions.cs	94.50% <0.00%> (+3.29%)	⬆️
...emetry.Api/Internal/OpenTelemetryApiEventSource.cs	82.35% <0.00%> (+8.82%)	⬆️
...xporter.OpenTelemetryProtocol/OtlpTraceExporter.cs	77.27% <0.00%> (+18.18%)	⬆️
src/OpenTelemetry/Logs/Pool/LogRecordSharedPool.cs	100.00% <0.00%> (+21.05%)	⬆️
...entation/ExportClient/OtlpGrpcTraceExportClient.cs	78.57% <0.00%> (+28.57%)	⬆️

[github-actions]

This PR was marked stale due to lack of activity and will be closed in 7 days. Commenting or Pushing will instruct the bot to automatically remove the label. This bot runs once per day.

[github-actions]

Closed as inactive. Feel free to reopen if this PR is still being worked on.