Performance diagnostics: Adds static timer and caches handler name

[j82w]

Pull Request Template

Description

Reduces allocation by 3.6% (32.58 KB to 31.38 KB) and latency by 1.6% (567.2 to 557.7us)

1. Reduces allocations by using a single static StopWatch instead of creating a new one for each DiagnosticScope.

This shows the performance results of getting latency from DateTime.UtcNow vs StopWatch vs StopWatch singleton

|                           Method |      Mean |    Error |   StdDev |   StdErr |       Min |        Q1 |    Median |        Q3 |       Max |         Op/s |  Gen 0 | Gen 1 | Gen 2 | Allocated |
|--------------------------------- |----------:|---------:|---------:|---------:|----------:|----------:|----------:|----------:|----------:|-------------:|-------:|------:|------:|----------:|
|           TimerDateTimeBenchmark | 126.48 ns | 0.974 ns | 1.427 ns | 0.265 ns | 123.96 ns | 125.31 ns | 126.55 ns | 127.93 ns | 128.65 ns |  7,906,436.0 |      - |     - |     - |         - |
|          TimerStopWatchBenchmark |  43.71 ns | 1.055 ns | 1.578 ns | 0.288 ns |  41.48 ns |  42.16 ns |  43.56 ns |  45.07 ns |  46.21 ns | 22,879,040.6 | 0.0063 |     - |     - |      40 B |
| TimerStopWatchSingletonBenchmark |  41.06 ns | 0.374 ns | 0.559 ns | 0.102 ns |  40.18 ns |  40.58 ns |  41.00 ns |  41.65 ns |  42.15 ns | 24,355,020.1 |      - |     - |     - |         - |

2. Reduces allocations and latency by caching the handler name instead of getting it for each call.

The MockedItemBenchmark.ReadItemExists results:

|            Method |      Type |     Mean |   Error |   StdDev |  StdErr |   Median |      Min |       Q1 |       Q3 |      Max |      P80 |      P85 |      P90 |      P95 |     P100 |    Op/s | Completed Work Items | Lock Contentions | Gen 0 | Gen 1 | Gen 2 | Allocated |
|------------------ |---------- |---------:|--------:|---------:|--------:|---------:|---------:|---------:|---------:|---------:|---------:|---------:|---------:|---------:|---------:|--------:|---------------------:|-----------------:|------:|------:|------:|----------:|
|    ReadItemExists |    Stream | 557.7 us | 6.63 us | 61.43 us | 2.01 us | 531.8 us | 468.9 us | 514.3 us | 598.3 us | 779.6 us | 620.9 us | 638.5 us | 654.6 us | 675.0 us | 779.6 us | 1,793.0 |               1.0000 |                - |     - |     - |     - |  30.66 KB |
| ReadItemExistsOld |    Stream | 567.2 us | 7.19 us | 66.38 us | 2.18 us | 543.3 us | 464.3 us | 518.9 us | 621.1 us | 796.6 us | 637.4 us | 652.7 us | 667.8 us | 697.0 us | 796.6 us | 1,763.2 |               1.0000 |                - |     - |     - |     - |  32.38 KB |
|    ReadItemExists |       OfT | 574.1 us | 6.36 us | 58.74 us | 1.93 us | 552.4 us | 496.2 us | 531.4 us | 599.5 us | 784.7 us | 637.2 us | 658.3 us | 670.5 us | 690.2 us | 784.7 us | 1,742.0 |               1.0000 |                - |     - |     - |     - |  38.32 KB |
| ReadItemExistsOld |       OfT | 583.7 us | 6.74 us | 61.98 us | 2.04 us | 560.5 us | 488.7 us | 538.9 us | 617.1 us | 828.9 us | 645.4 us | 662.9 us | 683.5 us | 700.5 us | 828.9 us | 1,713.3 |               1.0000 |                - |     - |     - |     - |  38.63 KB |
|    ReadItemExists | OfTCustom | 573.0 us | 5.61 us | 51.19 us | 1.70 us | 555.1 us | 490.3 us | 538.9 us | 590.7 us | 746.5 us | 604.4 us | 623.9 us | 663.6 us | 689.4 us | 746.5 us | 1,745.3 |               1.0000 |                - |     - |     - |     - |  38.33 KB |
| ReadItemExistsOld | OfTCustom | 608.4 us | 8.14 us | 75.27 us | 2.47 us | 579.5 us | 503.3 us | 557.3 us | 647.4 us | 927.8 us | 673.9 us | 692.9 us | 726.9 us | 764.8 us | 927.8 us | 1,643.6 |               1.0000 |                - |     - |     - |     - |  39.52 KB |

Type of change

Please delete options that are not relevant.

• [] Bug fix (non-breaking change which fixes an issue)
• [] New feature (non-breaking change which adds functionality)
• [] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [] This change requires a documentation update

Closing issues

To automatically close an issue: closes #IssueNumber

[ghost]

Closing due to in-activity, pease feel free to re-open.