Forum Stats

  • 3,839,356 Users
  • 2,262,486 Discussions
  • 7,900,947 Comments

Discussions

Help about understand values retrieved by Tom Kyte script for my LOB segment

trajon
trajon Member Posts: 58 Blue Ribbon
edited Jan 23, 2015 4:14AM in General Database Discussions

I have LOB segment. When I use Tom Kyte script show_space

(https://asktom.oracle.com/pls/apex/f?p=100:11:0::::P11_QUESTION_ID:14339684180676) a have this output:

Unformatted Blocks .....................             107

FS1 Blocks (0-25)  .....................               0

FS2 Blocks (25-50) .....................               0

FS3 Blocks (50-75) .....................               0

FS4 Blocks (75-100).....................               0

Full Blocks        .....................         859,438

Total Blocks............................       1,746,304

Total Bytes.............................  14,305,722,368

Total MBytes............................          13,643

Unused Blocks...........................               0

Unused Bytes............................               0

Last Used Ext FileId....................               5

Last Used Ext BlockId...................       1,261,056

Last Used Block.........................             128

I have only Full Blocks = 859,438, but Total Blocks = 1,746,304 why so?

spiderwoman

Best Answer

  • Jonathan Lewis
    Jonathan Lewis Member Posts: 10,010 Blue Diamond
    Answer ✓

    It looks like you chunk size is 16KB - Oracle seems to look only at the chunk headers in this code; so you would expect the raw segment's number of blocks to be twice the space "blocks" that this report produces if you're running an 8KB block size and a 16KB chunk size.

    Regards

    Jonathan Lewis

Answers

This discussion has been closed.