While I create non standart db_block_size tablespace I faced ORA-29339: tablespace block size 16384 does not match configured block sizes. 16k = 16*1024 = 16384 SQL> CREATE TABLESPACE DATA DATAFILE '/u01/app/oracle/oradata/cdb1/TEST/data01.dbf' SIZE 100M AUTOEXTEND ON NEXT 10M MAXSIZE 31G LOGGING DEFAULT NO INMEMORY EXTENT MANAGEMENT LOCAL AUTOALLOCATE BLOCKSIZE 16K SEGMENT SPACE MANAGEMENT AUTO FLASHBACK ON; ORA-29339 SQL> select name, block_size, current_size from v$buffer_pool; NAME BLOCK_SIZE CURRENT_SIZE -------------------- ---------- ------------ DEFAULT 8192 132096 Check db_*k_cache_size parameters SQL> show parameter cache_size NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ client_result_cache_size big integer 0 db_16k_cache_size big integer 0 db_2k_cache_size big integer 0 db_32k_cache_size bi...