Jackie-Jiang commented on pull request #6262:
URL: https://github.com/apache/incubator-pinot/pull/6262#issuecomment-730730910


   @siddharthteotia Please check my reply under the comments. I think the tests 
are quite thorough, and covers all the bits and different start indices.
   
   For your questions:
   
   > Is it correct to say that new bulk read32() will be used here only if the 
docIDs array has sequential (consecutive) ids. Otherwise, we will use the new 
single read APIs?
   
   Yes
   
   > The readUnchecked() has the potential to segfault / core dump?
   
   If you use readUnchecked() for the last 2 values, it can read over the 
boundary (explained in the javadoc). This is handled within the 
`FixedBitSVForwardIndexReaderV2`
   
   > There is a chance that perf wise, we might see -ve impact due to memcpy 
(especially for high throughput use cases). So for this API at least, I don't 
think JMH is a reasonable indicator of better performance always. It is 
worthwhile to do validation on a prod-like workload.
   
   Why is memcpy involved here? The new reader won't read extra values because 
the bulk read is only used for sequential ids. I already asked @pradeepgv42 to 
try this, and he confirmed up to 45% query latency drop comparing with the 
current reader. 


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