Here are the 20 whitepapers to understand the innovation of new technology and motivation.

1. Zanzibar (Google)

   https://www.usenix.org/system/files/atc19-pang.pdf

2. Amazon DynamoDB (Amazon)

   https://www.usenix.org/system/files/atc22-elhemali.pdf

3. Gorilla DB (Facebook)

   https://www.vldb.org/pvldb/vol8/p1816-teller.pdf

4. Monarch (Google)

   https://www.vldb.org/pvldb/vol13/p3181-adams.pdf

5. Memcached (Facebook)

   https://www.usenix.org/system/files/conference/nsdi13/nsdi13-final170_update.pdf

6. TAO (Meta)

   https://www.usenix.org/system/files/conference/atc13/atc13-bronson.pdf

7. Google File System (Google)

   https://research.google.com/archive/gfs-sosp2003.pdf

8. MapReduce (Google)

   https://research.google.com/archive/mapreduce-osdi04.pdf

9. Bigtable (Google)

   https://research.google.com/archive/bigtable-osdi06.pdf

10. Megastore (Google)

    https://research.google.com/pubs/megastore-providing-scalable-highly-available-storage-for-interactive-services/

11. Chubby (Google)

    https://research.google.com/archive/chubby-osdi06.pdf

12. Dapper (Google)

    https://research.google.com/pubs/dapper-a-large-scale-distributed-systems-tracing-infrastructure/

13. Pregel (Google)

    (Not explicitly found; usually cited as "Pregel: A System for Large-Scale Graph Processing" in ACM SIGMOD 2010; you can find it in academic repositories)

14. Amazon Aurora (Amazon)

    https://pages.cs.wisc.edu/~yxy/cs764-f20/papers/aurora-sigmod-17.pdf

15. FoundationDB (Apple)

    https://www.foundationdb.org/files/fdb-paper.pdf

16. Cassandra (Apache)

    https://www.cs.cornell.edu/projects/ladis2009/papers/lakshman-ladis2009.pdf

17. Minesweeper (Meta)

    https://research.ed.ac.uk/files/258551364/MineSweeper_ERDOS_DOA15112021_VOR_CC_BY.pdf

18. Spanner (Google)

    https://research.google.com/archive/spanner-osdi2012.pdf

19. FlexiRaft (Meta)

    https://vldb.org/cidrdb/papers/2023/p83-yadav.pdf