Cosmos Paged flux initial POC implementation v4

[kushagraThapar]

• CosmosPagedFlux initial POC implementation
• To get early feedback and scope the changes to a small subset of files, this PR only covers one API -> queryItems()

[kushagraThapar]

/azp run java - cosmos - tests

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[moderakh]

some questions:

1. Aren't we going to split the options as discussed earlier?
2. can you please run a perf benchmark with and without this PR using this benchmark, and see how different the numbers are?
   #6771

[kushagraThapar]

/azp run java - cosmos - tests

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[kushagraThapar]

/azp run java - cosmos - tests

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[kushagraThapar]

/azp run java - cosmos - tests

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[kushagraThapar]

some questions:

1. Aren't we going to split the options as discussed earlier?
2. can you please run a perf benchmark with and without this PR using this benchmark, and see how different the numbers are?
   v4: adds an in clause query benchmark #6771

As discussed over call, we will split the FeedOptions last when all the public surface API changes are finished.
Regarding perf, I am seeing same numbers with / without Cosmos Paged Flux implementation.

On feature/cosmos/v4 - WITHOUT Cosmos Paged Flux Implementation:

-- Meters ----------------------------------------------------------------------
#Successful Operations
             count = 10000
         mean rate = 31.13 events/second
     1-minute rate = 31.11 events/second
     5-minute rate = 29.16 events/second
    15-minute rate = 27.12 events/second
#Unsuccessful Operations
             count = 0
         mean rate = 0.00 events/second
     1-minute rate = 0.00 events/second
     5-minute rate = 0.00 events/second
    15-minute rate = 0.00 events/second

-- Timers ----------------------------------------------------------------------
Latency
             count = 10000
         mean rate = 31.13 calls/second
     1-minute rate = 31.11 calls/second
     5-minute rate = 29.16 calls/second
    15-minute rate = 27.12 calls/second
               min = 121.16 milliseconds
               max = 573.10 milliseconds
              mean = 323.81 milliseconds
            stddev = 76.05 milliseconds
            median = 336.66 milliseconds
              75% <= 375.86 milliseconds
              95% <= 429.23 milliseconds
              98% <= 454.12 milliseconds
              99% <= 469.30 milliseconds
            99.9% <= 522.05 milliseconds

Cosmos Paged Flux Implementation:

-- Meters ----------------------------------------------------------------------
#Successful Operations
             count = 10000
         mean rate = 30.45 events/second
     1-minute rate = 30.43 events/second
     5-minute rate = 28.40 events/second
    15-minute rate = 26.24 events/second
#Unsuccessful Operations
             count = 0
         mean rate = 0.00 events/second
     1-minute rate = 0.00 events/second
     5-minute rate = 0.00 events/second
    15-minute rate = 0.00 events/second

-- Timers ----------------------------------------------------------------------
Latency
             count = 10000
         mean rate = 30.45 calls/second
     1-minute rate = 30.43 calls/second
     5-minute rate = 28.40 calls/second
    15-minute rate = 26.24 calls/second
               min = 118.10 milliseconds
               max = 571.99 milliseconds
              mean = 326.78 milliseconds
            stddev = 67.36 milliseconds
            median = 331.55 milliseconds
              75% <= 372.05 milliseconds
              95% <= 425.15 milliseconds
              98% <= 454.38 milliseconds
              99% <= 486.39 milliseconds
            99.9% <= 571.99 milliseconds

[kushagraThapar]

/azp run java - cosmos - tests

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[kushagraThapar]

/azp run java - cosmos - tests

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[moderakh]

LGTM.

just please note CosmosPagedFluxOptions still is in the public package not implementation.
Also for the new tests on backpressure, do they pass as they are? do they need any threshold massaging?

[kushagraThapar]

/azp run java - cosmos - tests

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[kushagraThapar]

/azp run java - cosmos - tests

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[kushagraThapar]

known failures, merging this in now.