Remove the construction of second bitmap in text index reader to improve performance

[siddharthteotia]

This is a follow-up to optimization implemented in PR #5177.

Since we now have pre-built mapping of luceneDocId to pinotDocId, we can directly build the result bitmap with pinotDocId. This PR removes the construction of second bitmap since earlier we had to do build the result in two phases -- (1) run search query to get luceneDocIDs in a bitmap. Iterate over this bitmap and build a second bitmap with corresponding pinotDocIds.

Now in our Lucene collector callback, we can directly build the final bitmap.

This change along with previous PR provides significant performance improvements.

Ran an increasingQPS test on real data (single segment with 10million docs and a text index). QPS was increased from 1 to 40

REPORT FOR TARGET QPS: 1.0
Current Target QPS: 1.0, Time Passed: 30084ms, Queries Executed: 30, Average QPS: 0.997207818109294, Average Broker Time: 44.6ms, Average Client Time: 50.1ms, Queries Queued: 0.

REPORT FOR TARGET QPS: 3.0
Current Target QPS: 3.0, Time Passed: 30255ms, Queries Executed: 90, Average QPS: 2.974714923153198, Average Broker Time: 50.3ms, Average Client Time: 53.24444444444445ms, Queries Queued: 0.

REPORT FOR TARGET QPS: 5.0
Current Target QPS: 5.0, Time Passed: 30412ms, Queries Executed: 150, Average QPS: 4.932263580165724, Average Broker Time: 41.44ms, Average Client Time: 44.1ms, Queries Queued: 0.

REPORT FOR TARGET QPS: 7.0
Current Target QPS: 7.0, Time Passed: 30489ms, Queries Executed: 210, Average QPS: 6.887730000983961, Average Broker Time: 41.82857142857143ms, Average Client Time: 44.00476190476191ms, Queries Queued: 0.

REPORT FOR TARGET QPS: 9.0
Current Target QPS: 9.0, Time Passed: 30868ms, Queries Executed: 270, Average QPS: 8.746922379162887, Average Broker Time: 43.385185185185186ms, Average Client Time: 45.27037037037037ms, Queries Queued: 0.

REPORT FOR TARGET QPS: 25.0
Current Target QPS: 25.0, Time Passed: 30233ms, Queries Executed: 694, Average QPS: 22.955049118512882, Average Broker Time: 37.27089337175793ms, Average Client Time: 38.53746397694525ms, Queries Queued: 0.

REPORT FOR TARGET QPS: 27.0
Current Target QPS: 27.0, Time Passed: 30254ms, Queries Executed: 740, Average QPS: 24.459575593309975, Average Broker Time: 39.71351351351351ms, Average Client Time: 40.87837837837838ms, Queries Queued: 0.

REPORT FOR TARGET QPS: 29.0
Current Target QPS: 29.0, Time Passed: 30147ms, Queries Executed: 798, Average QPS: 26.4702955517962, Average Broker Time: 37.06516290726817ms, Average Client Time: 38.22431077694235ms, Queries Queued: 0.

REPORT FOR TARGET QPS: 31.0
Current Target QPS: 31.0, Time Passed: 30160ms, Queries Executed: 843, Average QPS: 27.950928381962864, Average Broker Time: 37.79359430604982ms, Average Client Time: 38.86476868327402ms, Queries Queued: 0.

FINAL REPORT:
Current Target QPS: 39.0, Time Passed: 27344ms, Queries Executed: 947, Average QPS: 34.632826214160325, Average Broker Time: 36.91024287222809ms, Average Client Time: 37.91129883843717ms.

10th percentile: 4.0
25th percentile: 26.0
50th percentile: 37.0
90th percentile: 68.0
95th percentile: 75.0
99th percentile: 129.0
99.9th percentile: 150.0

The optimizations implemented in this and previous PR are not directly applicable to realtime (we have the exact same performance overhead in realtime too) since we can't have a pre-built mapping there. We mostly need to build a cache on-the-fly as queries are processed on realtime lucene index. A solution is in progress. Will put PR soon

[Jackie-Jiang]

I would recommend implementing the real-time docId translator instead of having a separate real-time collector. You can also do that as the next step.
LGTM otherwise.

[Jackie-Jiang]

(OCD) Can we always use docId for naming instead of mixing use of docId and docID

[siddharthteotia]

I would recommend implementing the real-time docId translator instead of having a separate real-time collector. You can also do that as the next step.
LGTM otherwise.

Yes, that is the next step (implementing this optimization for realtime)

[siddharthteotia]

(OCD) Can we always use docId for naming instead of mixing use of docId and docID

Done.