这里给出位于free list上的block dump的片段
block header dump: 0x03c00235
object id on block? y
seg/obj: 0xe2d8 csc: 0x00.6264c61 itc: 1 flg: o typ: 1 - data
fsl: 1 fnx: 0x3c00234 ver: 0x01
==> seg/obj object id in dictionary
==> csc scn of last block cleanout
==> itc number of itl slots
==> flg o = on freelist , - = not on freelist
==> typ 1 = data 2 = index
==> fsl
==> fnx dba of next block on freelist
举例来说如果有五个块在free list中，分别为a,b,c,d,e
就会形成segment header->a->b->c->d->e--|
