Re: 8.1.7 cache buffer chains contention

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in <999014469.27908.1.nnrp-07.9e984b29_at_news.demon.co.uk>:

>That's a bit odd, I would have expected to
>see at least a couple of CR copies of the block.
>
>Is the index in the DEFAULT pool, or one or
>other of the KEEP / RECYCLE pools ?

In the default pool.

>
>Has your value for _db_block_max_cr_dba
>been adjusted.

No it hasnt, the default is 6

>
>How do you feel about doing:
>
> alter session set events
> 'immediate trace name treedump level NNN';
>
>where NNN is the object_id of the index in question.
>This will dump a line of text for every block in the
>index, and prove that the block IS the root block
>(it will be the first one listed in the dumpt) as well
>as telling us something about the degree of packing
>of the block and the rest of the index.
>

Results of dump. Not sure how much you wanted to see..

Machine: alpha
Instance name: P013
Redo thread mounted by this instance: 1
Oracle process number: 528
Unix process pid: 22118, image: oracle_at_prd0db05 (TNS V1-V3)

• 2001-08-28 13:36:31.358
• SESSION ID:(547.893) 2001-08-28 13:36:31.251 ----- begin tree dump branch: 0x4803e803 1208215555 (0: nrow: 61, level: 3) branch: 0x4803fe24 1208221220 (-1: nrow: 44, level: 2) branch: 0x4803e876 1208215670 (-1: nrow: 67, level: 1) leaf: 0x4803e804 1208215556 (-1: nrow: 92 rrow: 92) Leaf block dump

  ---

  header address 18186911836=0x43c06405c kdxcolev 0 kdxcolok 0 kdxcoopc 0x80: opcode=0: iot flags=--- is converted=Y kdxconco 6 kdxcosdc 0 kdxconro 92 kdxcofbo 220=0xdc kdxcofeo 292=0x124 kdxcoavs 72 kdxlespl 0 kdxlende 0 kdxlenxt 1208215557=0x4803e805 kdxleprv 0=0x0 kdxledsz 0 kdxlebksz 3920 row#0[3872] flag: -----, lock: 0 col 0; len 15; (15): 2b 2b 55 4d 3a 43 41 4e 32 32 39 32 30 30 43 col 1; len 3; (3): 31 30 30 col 2; len 7; (7): 77 64 01 01 01 01 01 col 3; len 7; (7): 78 c7 0c 1f 01 01 01 col 4; len 2; (2): c1 60 col 5; len 6; (6): 34 01 83 bb 00 07 row#1[3824] flag: -----, lock: 0 col 0; len 15; (15): 2b 2b 55 4d 3a 4d 41 54 32 39 36 38 36 31 42 col 1; len 3; (3): 31 30 30 col 2; len 7; (7): 77 64 01 01 01 01 01