X $ bh

X $ bh

X$BH Fixed Table Buffer Cache Diagram Column Type Description~~~~~~ ~~~~~ ~~~~~~~~~~~ADDR RAW(4) Hex address of the Buffer Header.INDX NUMBER Buffer Header numberBUF# NUMBERHLADDR RAW(4) Hash Chain Latch AddressSee . ADDRLRU_FLAG NUMBER 8.1+ LRU flagKCBBHLDF 0x01 8.1 LRU Dump Flag used in debug print routineKCBBHLMT 0x02 8.1 moved to tail of lru (for extended stats) KCBBHLAL 0x04 8.1 on auxiliary list KCBBHLHB 0x08 8.1 hot buffer - not in cold portion of lru FLAG NUMBER KCBBHFBD 0x00001 buffer dirty KCBBHFAM 0x00002 7.3 about to modify; try not to start io KCBBHFAM 0x00002 8.0 about to modify; try not to start io KCBBHNAC 0x00002 8.1 notify dbwr after change KCBBHFMS 0x00004 modification started, no new writesKCBBHFBL 0x00008 block logged KCBBHFTD 0x00010 temporary data - no redo for changes KCBBHFBW 0x00020 being written; can't modify KCBBHFWW 0x00040 waiting for write to finishKCBBHFCK 0x00080 7.3 checkpoint asap 0x00080 8.0 not usedKCBBHFMW 0x00080 8.1 multiple waiters when gc lock acquiredKCBBHFRR 0x00100 recovery reading, do not reuse, being read KCBBHFUL 0x00200 unlink from lock element - make non-currentKCBBHFDG 0x00400 write block & stop using for lock down gradeKCBBHFCW 0x00800 write block for cross instance callKCBBHFCR 0x01000 reading from disk into KCBBHCR bufferKCBBHFGC 0x02000 has been gotten in current modeKCBBHFST 0x04000 stale - unused CR buf made from current0x08000 7.3 Not used.KCBBHFDP 0x08000 8.0 deferred pingKCBBHFDP 0x08000 8.1 deferred pingKCBBHFDA 0x10000 Direct Access to buffer contentsKCBBHFHD 0x20000 Hash chain Dump used in debug print routineKCBBHFIR 0x40000 Ignore Redo for instance recovery KCBBHFSQ 0x80000 sequential scan only flagKCBBHFNW 0x100000 7.3 Set to indicate a buffer that is NEW0x100000 8.0 Not usedKCBBHFBP 0x100000 8.1 Indicates that buffer was prefetched KCBBHFRW 0x200000 7.3 re-write if being written (sort) 0x200000 8.0 Not usedKCBBHFFW 0x200000 8.1 Buffer has been written onceKCBBHFFB 0x400000 buffer is "logically" flushed KCBBHFRS 0x800000 ReSilvered already - do not redirty KCBBHFKW 0x1000000 7.3 ckpt writing flag to avoid rescan */0x1000000 8.0 Not usedKCBBHDRC 0x1000000 8.1 buffer is nocache 0x2000000 7.3 Not usedKCBBHFRG 0x2000000 8.0 Redo Generated since block read KCBBHFRG 0x2000000 8.1 Redo Generated since block read KCBBHFWS 0x10000000 8.0 Skipped write for checkpoint. KCBBHFDB 0x20000000 8.1 buffer is directly from a foreign DB KCBBHFAW 0x40000000 8.0 Flush after writing KCBBHFAW 0x40000000 8.1 Flush after writing TS# NUMBER 8.X Tablespace numberDBARFIL NUMBER 8.X Relative file number of blockDBAFIL NUMBER 7.3 File number of blockDBABLK NUMBER Block number of blockCLASS NUMBER See Note 33434.1STATE NUMBER KCBBHFREE 0 buffer free KCBBHEXLCUR 1 buffer current (and if DFS locked X) KCBBHSHRCUR 2 buffer current (and if DFS locked S)KCBBHCR 3 buffer consistant read KCBBHREADING 4 Being read KCBBHMRECOVERY 5 media recovery (current & special) KCBBHIRECOVERY 6 Instance recovery (somewhat special)MODE_HELD NUMBER Mode buffer held in (MODE pre 7.3)0=KCBMNULL, KCBMSHARE, KCBMEXCLCHANGES NUMBERCSTATE NUMBERX_TO_NULL NUMBER Count of PINGS out (OPS)DIRTY_QUEUE NUMBER You wont normally see buffers on the LRUWLE_ADDR RAW(4) Lock Element address (OPS)SET_DS RAW(4) Buffer cache set this buffer is underOBJ NUMBER Data object number TCH NUMBER 8.1 Touch CountTIM NUMBER 8.1 Touch TimeBA RAW(4)CR_SCN_BAS NUMBER Consistent Read SCN baseCR_SCN_WRP NUMBER Consistent Read SCN wrapCR_XID_USN NUMBER CR XID Undo segment noCR_XID_SLT NUMBER CR XID slotCR_XID_SQN NUMBER CR XID SequenceCR_UBA_FIL NUMBER CR UBA fileCR_UBA_BLK NUMBER CR UBA BlockCR_UBA_SEQ NUMBER CR UBA sequenceCR_UBA_REC NUMBER CR UBA recordCR_SFL NUMBERLRBA_SEQ NUMBER } Lowest RBA needed to recover block in cacheLRBA_BNO NUMBER }LRBA_BOF NUMBER }HRBA_SEQ NUMBER } Redo RBA to be flushed BEFORE this block HRBA_BNO NUMBER } can be written outHRBA_BOF NUMBER }RRBA_SEQ NUMBER } Block recovery RBARRBA_BNO NUMBER }RRBA_BOF NUMBER }NXT_HASH NUMBER Next buffer on this hash chainPRV_HASH NUMBER Previous buffer on this hash chainNXT_LRU NUMBER Next buffer on the LRUPRV_LRU NUMBER Previous buffer on the LRUUS_NXT RAW(4)US_PRV RAW(4)WA_NXT RAW(4)WA_PRV RAW(4)ACC RAW(4)MOD RAW(4)