feat: enhance the capping of max spans per trace at global level

[kotharironak]

The rawSpanGrouper, stitch the spans into traces. To cap the number of spans per tace, currently, we have config that controls per-tenant level. e.g

max.span.count = {
  tenant1 = 5
}

As part of this PR, we are enhancing this scheme by adding a global upper limit. As shown in the below example config, tenant1 is applying 5 spans/trace limit, but for other tenants (say tenant2), it will apply 6 spans/trace limit.

default.max.span.count = 6
max.span.count = {
  tenant1 = 5
}

[codecov]

Codecov Report

Merging #290 (56dc177) into main (efa5d17) will increase coverage by 0.15%.
The diff coverage is 86.66%.

@@             Coverage Diff              @@
##               main     #290      +/-   ##
============================================
+ Coverage     79.44%   79.60%   +0.15%     
- Complexity     1265     1268       +3     
============================================
  Files           112      112              
  Lines          4934     4937       +3     
  Branches        452      451       -1     
============================================
+ Hits           3920     3930      +10     
+ Misses          812      806       -6     
+ Partials        202      201       -1     

Flag	Coverage Δ
unit	79.60% <86.66%> (+0.15%)	⬆️

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Impacted Files	Coverage Δ
.../core/rawspansgrouper/RawSpanGrouperConstants.java	0.00% <ø> (ø)
...rtrace/core/rawspansgrouper/RawSpansProcessor.java	81.57% <86.66%> (+6.80%)	⬆️

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[kotharironak]

As we already have max.span.count for per tenant, didn't go for max.span.count.upper.limit as config. Let me know if you have a better name.

[avinashkolluru]

I think we should call this default.max.span.count and the below section can be used as an override per tenant.

[kotharironak]

This makes sense. Made changes.

[github-actions]

Unit Test Results

  74 files  ±0    74 suites  ±0   1m 2s ⏱️ -2s
392 tests ±0  392 ✔️ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit cdbd7b4. ± Comparison against base commit efa5d17.

[avinashkolluru]

I thought tenant specific config acts as an override the default.
But the condition here doesn't seem to indicate that. We are picking the least of both.

[kotharironak]

What @ravisingal & I had discussed offline of having a global upper limit, and so I had prior notatin of upper.max.span.count. But, what you are saying is that for a specific tenant, we want a higher limit, that makes sense.

Let me know @avinashkolluru @ravisingal if we want to modify and go with that if that is making more sense.

[avinashkolluru]

I'd suggest made the tenant specific config as an override. It shouldn't matter whether its is lower or higher than the default.