Cache Buffer chains on Index

Hi Team,

During peak business hours I am getting cache buffer chains issue.

I did some R&D and found that each of the session and sqlid is leading me to one index which is a normal BTree index.

How can I resolve the issue?

During non business hours the query is executing in seconds.

Output

STATE                            BLOCK_CLASS                      OBJECT_TYPE         object                                          TCH  MODE_HELD DIRTY                            TEMP                             PING

-------------------------------- -------------------------------- ------------------- ---------------------------------------- ---------- ---------- -------------------------------- -------------------------------- --------------------------------

STALE                            DIRECT

-------------------------------- --------------------------------

FLG_LRUFLG

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

        DQ

----------

scur                             data block                       INDEX               USERNAME.INDEX_NAME   31          0 N                                N                                N

N                                N

0:8

Thank you