????????«MINSCN?Cache Fusion Read Consistent» ????,????????????

??????????????????:

SQL> select * from V$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
PL/SQL Release 11.2.0.3.0 - Production
CORE    11.2.0.3.0      Production
TNS for Linux: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production

SQL> select count(*) from gv$instance;

  COUNT(*)
----------
         2

SQL> select * from global_name;

GLOBAL_NAME
--------------------------------------------------------------------------------
www.oracledatabase12g.com

?11gR2 2??RAC??????????status???XG,????Xcurrent block???INSTANCE 2?hold?,?????INSTANCE 1?????????,?????:

SQL> select  * from test;

        ID
----------
         1
         2

SQL> select dbms_rowid.rowid_block_number(rowid),dbms_rowid.rowid_relative_fno(rowid) from test;

DBMS_ROWID.ROWID_BLOCK_NUMBER(ROWID) DBMS_ROWID.ROWID_RELATIVE_FNO(ROWID)
------------------------------------ ------------------------------------
                               89233                                    1
                               89233                                    1

SQL> alter system flush buffer_cache;

System altered.

INSTANCE 1 Session A:

SQL>  update test set id=id+1 where id=1;

1 row updated.

INSTANCE 1 Session B:

SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0;

     STATE CR_SCN_BAS
---------- ----------
         1          0
         3    1755287

SQL> oradebug setmypid;
Statement processed.
SQL> oradebug dump gc_elements 255;
Statement processed.
SQL> oradebug tracefile_name;
/s01/orabase/diag/rdbms/vprod/VPROD1/trace/VPROD1_ora_19111.trc

GLOBAL CACHE ELEMENT DUMP (address: 0xa4ff3080):
  id1: 0x15c91 id2: 0x1 pkey: OBJ#76896 block: (1/89233)
  lock: X rls: 0x0 acq: 0x0 latch: 3
  flags: 0x20 fair: 0 recovery: 0 fpin: 'kdswh11: kdst_fetch'
  bscn: 0x0.146e20 bctx: (nil) write: 0 scan: 0x0
  lcp: (nil) lnk: [NULL] lch: [0xa9f6a6f8,0xa9f6a6f8]
  seq: 32 hist: 58 145:0 118 66 144:0 192 352 197 48 121 113 424 180 58
  LIST OF BUFFERS LINKED TO THIS GLOBAL CACHE ELEMENT:
    flg: 0x02000001 lflg: 0x1 state: XCURRENT tsn: 0 tsh: 2
      addr: 0xa9f6a5c8 obj: 76896 cls: DATA bscn: 0x0.1ac898
BH (0xa9f6a5c8) file#: 1 rdba: 0x00415c91 (1/89233) class: 1 ba: 0xa9e56000
  set: 5 pool: 3 bsz: 8192 bsi: 0 sflg: 3 pwc: 0,15
  dbwrid: 0 obj: 76896 objn: 76896 tsn: 0 afn: 1 hint: f
  hash: [0x91f4e970,0xbae9d5b8] lru: [0x91f58848,0xa9f6a828]
  lru-flags: debug_dump
  obj-flags: object_ckpt_list
  ckptq: [0x9df6d1d8,0xa9f6a740] fileq: [0xa2ece670,0xbdf4ed68] objq: [0xb4964e00,0xb4964e00] objaq: [0xb4964de0,0xb4964de0]
  st: XCURRENT md: NULL fpin: 'kdswh11: kdst_fetch' tch: 2 le: 0xa4ff3080
  flags: buffer_dirty redo_since_read
  LRBA: [0x19.5671.0] LSCN: [0x0.1ac898] HSCN: [0x0.1ac898] HSUB: [1]
  buffer tsn: 0 rdba: 0x00415c91 (1/89233)
  scn: 0x0000.001ac898 seq: 0x01 flg: 0x00 tail: 0xc8980601
  frmt: 0x02 chkval: 0x0000 type: 0x06=trans data

??????block: (1/89233)?GLOBAL CACHE ELEMENT DUMP?LOCK????X ??XG , ??????Current Block????Instance??modify???,?????????????

????Instance 2 ????:

Instance 2 Session C:

SQL> update test set id=id+1 where id=2;

1 row updated.

Instance 2 Session D:

SQL>  select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0;

     STATE CR_SCN_BAS
---------- ----------
         1          0
         3    1756658

SQL> oradebug setmypid;
Statement processed.
SQL> oradebug dump gc_elements 255;
Statement processed.
SQL> oradebug tracefile_name;
/s01/orabase/diag/rdbms/vprod/VPROD2/trace/VPROD2_ora_13038.trc

GLOBAL CACHE ELEMENT DUMP (address: 0x89fb25a0):
  id1: 0x15c91 id2: 0x1 pkey: OBJ#76896 block: (1/89233)
  lock: XG rls: 0x0 acq: 0x0 latch: 3
  flags: 0x20 fair: 0 recovery: 0 fpin: 'kduwh01: kdusru'
  bscn: 0x0.1acdf3 bctx: (nil) write: 0 scan: 0x0
  lcp: (nil) lnk: [NULL] lch: [0x96f4cf80,0x96f4cf80]
  seq: 61 hist: 324 21 143:0 19 16 352 329 144:6 14 7 352 197
  LIST OF BUFFERS LINKED TO THIS GLOBAL CACHE ELEMENT:
    flg: 0x0a000001 state: XCURRENT tsn: 0 tsh: 1
      addr: 0x96f4ce50 obj: 76896 cls: DATA bscn: 0x0.1acdf6
BH (0x96f4ce50) file#: 1 rdba: 0x00415c91 (1/89233) class: 1 ba: 0x96bd4000
  set: 5 pool: 3 bsz: 8192 bsi: 0 sflg: 2 pwc: 0,15
  dbwrid: 0 obj: 76896 objn: 76896 tsn: 0 afn: 1 hint: f
  hash: [0x96ee1fe8,0xbae9d5b8] lru: [0x96f4d0b0,0x96f4cdc0]
  obj-flags: object_ckpt_list
  ckptq: [0xbdf519b8,0x96f4d5a8] fileq: [0xbdf519d8,0xbdf519d8] objq: [0xb4a47b90,0xb4a47b90] objaq: [0x96f4d0e8,0xb4a47b70]
  st: XCURRENT md: NULL fpin: 'kduwh01: kdusru' tch: 1 le: 0x89fb25a0
  flags: buffer_dirty redo_since_read remote_transfered
  LRBA: [0x11.9e18.0] LSCN: [0x0.1acdf6] HSCN: [0x0.1acdf6] HSUB: [1]
  buffer tsn: 0 rdba: 0x00415c91 (1/89233)
  scn: 0x0000.001acdf6 seq: 0x01 flg: 0x00 tail: 0xcdf60601
  frmt: 0x02 chkval: 0x0000 type: 0x06=trans data

 GCS CLIENT 0x89fb2618,6 resp[(nil),0x15c91.1] pkey 76896.0
   grant 2 cvt 0 mdrole 0x42 st 0x100 lst 0x20 GRANTQ rl G0
   master 1 owner 2 sid 0 remote[(nil),0] hist 0x94121c601163423c
   history 0x3c.0x4.0xd.0xb.0x1.0xc.0x7.0x9.0x14.0x1.
   cflag 0x0 sender 1 flags 0x0 replay# 0 abast (nil).x0.1 dbmap (nil)
   disk: 0x0000.00000000 write request: 0x0000.00000000
   pi scn: 0x0000.00000000 sq[(nil),(nil)]
   msgseq 0x1 updseq 0x0 reqids[6,0,0] infop (nil) lockseq x2b8
   pkey 76896.0
   hv 93 [stat 0x0, 1->1, wm 32768, RMno 0, reminc 18, dom 0]
   kjga st 0x4, step 0.0.0, cinc 20, rmno 6, flags 0x0
   lb 0, hb 0, myb 15250, drmb 15250, apifrz 0

?Instance 2??????block: (1/89233)? GLOBAL CACHE ELEMENT Lock Convert?lock: XG

????GC_ELEMENTS DUMP???XCUR Cache Fusion?,???????X$ VIEW,??? X$LE X$KJBR X$KJBL, ???X$ VIEW???????????????????:

INSTANCE 2 Session D:

SELECT *
  FROM x$le
 WHERE le_addr IN (SELECT le_addr
                     FROM x$bh
                    WHERE obj IN (SELECT data_object_id
                                    FROM dba_objects
                                   WHERE owner = 'SYS'
                                     AND object_name = 'TEST')
                      AND class = 1
                      AND state != 3);

ADDR                   INDX    INST_ID LE_ADDR              LE_ID1     LE_ID2
---------------- ---------- ---------- ---------------- ---------- ----------
    LE_RLS     LE_ACQ   LE_FLAGS    LE_MODE   LE_WRITE   LE_LOCAL LE_RECOVERY
---------- ---------- ---------- ---------- ---------- ---------- -----------
   LE_BLKS    LE_TIME LE_KJBL
---------- ---------- ----------------
00007F94CA14CF60       7003          2 0000000089FB25A0      89233          1
         0          0         32          2          0          1           0
         1          0 0000000089FB2618

PCM Resource NAME?[ID1][ID2],[BL]???, ID1?ID2 ??blockno? fileno????, ??????????GC_elements dump?? id1: 0x15c91 id2: 0×1 pkey: OBJ#76896 block: (1/89233)?? ,?  kjblname ? kjbrname ??”[0x15c91][0x1],[BL]” ??:

INSTANCE 2 Session D:

SQL> set linesize 80 pagesize 1400
SQL> SELECT *
  2    FROM x$kjbl l
  3   WHERE l.kjblname LIKE '%[0x15c91][0x1],[BL]%';

ADDR                   INDX    INST_ID KJBLLOCKP        KJBLGRANT KJBLREQUE
---------------- ---------- ---------- ---------------- --------- ---------
  KJBLROLE KJBLRESP         KJBLNAME
---------- ---------------- ------------------------------
KJBLNAME2                       KJBLQUEUE
------------------------------ ----------
KJBLLOCKST                                                       KJBLWRITING
---------------------------------------------------------------- -----------
KJBLREQWRITE  KJBLOWNER KJBLMASTER KJBLBLOCKED KJBLBLOCKER    KJBLSID KJBLRDOMID
------------ ---------- ---------- ----------- ----------- ---------- ----------
  KJBLPKEY
----------
00007F94CA22A288        451          2 0000000089FB2618 KJUSEREX  KJUSERNL
         0 00               [0x15c91][0x1],[BL][ext 0x0,0x
89233,1,BL                              0
GRANTED                                                                    0
           0          1          0           0           0          0          0
     76896

SQL> SELECT r.* FROM x$kjbr r WHERE r.kjbrname LIKE '%[0x15c91][0x1],[BL]%';

no rows selected

Instance 1 session B:

SQL>  SELECT r.* FROM x$kjbr r WHERE r.kjbrname LIKE '%[0x15c91][0x1],[BL]%';

ADDR                   INDX    INST_ID KJBRRESP         KJBRGRANT KJBRNCVL
---------------- ---------- ---------- ---------------- --------- ---------
  KJBRROLE KJBRNAME                       KJBRMASTER KJBRGRANTQ
---------- ------------------------------ ---------- ----------------
KJBRCVTQ         KJBRWRITER          KJBRSID KJBRRDOMID   KJBRPKEY
---------------- ---------------- ---------- ---------- ----------
00007F801ACA68F8       1355          1 00000000B5A62AE0 KJUSEREX  KJUSERNL
         0 [0x15c91][0x1],[BL][ext 0x0,0x          0 00000000B48BB330
00               00                        0          0      76896

??????Instance 1???block: (1/89233),??????Instance 2 build cr block ????Instance 1, ?????????? ????? Instance 1? Foreground Process ? Instance 2?LMS??????RAC  TRACE:

Instance 2:

[oracle@vrh2 ~]$ ps -ef|grep ora_lms|grep -v grep
oracle   23364     1  0 Apr29 ?        00:33:15 ora_lms0_VPROD2

SQL> oradebug setospid 23364
Oracle pid: 13, Unix process pid: 23364, image: [email protected] (LMS0)

SQL> oradebug event 10046 trace name context forever,level 8:10708 trace name context forever,level 103: trace[rac.*] disk high;
Statement processed.

SQL> oradebug tracefile_name
/s01/orabase/diag/rdbms/vprod/VPROD2/trace/VPROD2_lms0_23364.trc

Instance 1 session B :

SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0;

     STATE CR_SCN_BAS
---------- ----------
         3    1756658
         3    1756661
         3    1755287

Instance 1 session A :

SQL> alter session set events '10046 trace name context forever,level 8:10708 trace name context forever,level 103: trace[rac.*] disk high';

Session altered.

SQL> select * from test;

        ID
----------
         2
         2

SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0;

     STATE CR_SCN_BAS
---------- ----------
         3    1761520

?x$BH?????,???????Instance 1???build??CR block,????? TRACE ??:

Instance 1 foreground Process:

PARSING IN CURSOR #140336527348792 len=18 dep=0 uid=0 oct=3 lid=0 tim=1335939136125254 hv=1689401402 ad='b1a4c828' sqlid='c99yw1xkb4f1u'
select * from test
END OF STMT
PARSE #140336527348792:c=2999,e=2860,p=0,cr=0,cu=0,mis=1,r=0,dep=0,og=1,plh=1357081020,tim=1335939136125253
EXEC #140336527348792:c=0,e=40,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=1,plh=1357081020,tim=1335939136125373
WAIT #140336527348792: nam='SQL*Net message to client' ela= 6 driver id=1650815232 #bytes=1 p3=0 obj#=0 tim=1335939136125420

*** 2012-05-02 02:12:16.125
kclscrs: req=0 block=1/89233
2012-05-02 02:12:16.125574 : kjbcro[0x15c91.1 76896.0][4]

*** 2012-05-02 02:12:16.125
kclscrs: req=0 typ=nowait-abort

*** 2012-05-02 02:12:16.125
kclscrs: bid=1:3:1:0:f:1e:0:0:10:0:0:0:1:2:4:1:20:0:0:0:c3:49:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:4:3:2:1:2:0:1c:0:4d:26:a3:52:0:0:0:0:c7:c:ca:62:c3:49:0:0:0:0:1:0:14:8e:47:76:1:2:dc:5:a9:fe:17:75:0:0:0:0:0:0:0:0:0:0:0:0:99:ed:0:0:0:0:0:0:10:0:0:0
2012-05-02 02:12:16.125718 : kjbcro[0x15c91.1 76896.0][4]
2012-05-02 02:12:16.125751 : GSIPC:GMBQ: buff 0xba0ee018, queue 0xbb79a7b8, pool 0x60013fa0, freeq 0, nxt 0xbb79a7b8, prv 0xbb79a7b8
2012-05-02 02:12:16.125780 : kjbsentscn[0x0.1ae0f0][to 2]
2012-05-02 02:12:16.125806 : GSIPC:SENDM: send msg 0xba0ee088 dest x20001 seq 177740 type 36 tkts xff0000 mlen x1680198
2012-05-02 02:12:16.125918 : kjbmscr(0x15c91.1)reqid=0x8(req 0xa4ff30f8)(rinst 1)hldr 2(infosz 200)(lseq x2b8)
2012-05-02 02:12:16.126959 : GSIPC:KSXPCB: msg 0xba0ee088 status 30, type 36, dest 2, rcvr 1

*** 2012-05-02 02:12:16.127
kclwcrs: wait=0 tm=1233

*** 2012-05-02 02:12:16.127
kclwcrs: got 1 blocks from ksxprcv
WAIT #140336527348792: nam='gc cr block 2-way' ela= 1233 p1=1 p2=89233 p3=1 obj#=76896 tim=1335939136127199
2012-05-02 02:12:16.127272 : kjbcrcomplete[0x15c91.1 76896.0][0]
2012-05-02 02:12:16.127309 : kjbrcvdscn[0x0.1ae0f0][from 2][idx 2012-05-02 02:12:16.127329 : kjbrcvdscn[no bscn <= rscn 0x0.1ae0f0][from 2]

???? kjbcro[0x15c91.1 76896.0][4] kjbsentscn[0x0.1ae0f0][to 2] ?Instance 2??SCN=1ae0f0=1761520? block: (1/89233),???’gc cr block 2-way’ ??,?????????CR block?

Instance 2 LMS TRACE

2012-05-02 02:12:15.634057 : GSIPC:RCVD: ksxp msg 0x7f16e1598588 sndr 1 seq 0.177740 type 36 tkts 0
2012-05-02 02:12:15.634094 : GSIPC:RCVD: watq msg 0x7f16e1598588 sndr 1, seq 177740, type 36, tkts 0
2012-05-02 02:12:15.634108 : GSIPC:TKT: collect msg 0x7f16e1598588 from 1 for rcvr -1, tickets 0
2012-05-02 02:12:15.634162 : kjbrcvdscn[0x0.1ae0f0][from 1][idx 2012-05-02 02:12:15.634186 : kjbrcvdscn[no bscn1, wm 32768, RMno 0, reminc 18, dom 0]
   kjga st 0x4, step 0.0.0, cinc 20, rmno 6, flags 0x0
   lb 0, hb 0, myb 15250, drmb 15250, apifrz 0
 GCS CLIENT END
2012-05-02 02:12:15.635211 : kjbdowncvt[0x15c91.1 76896.0][1][options x0]
2012-05-02 02:12:15.635230 : GSIPC:AMBUF: rcv buff 0x7f16e1c56420, pool rcvbuf, rqlen 1103
2012-05-02 02:12:15.635308 : GSIPC:GPBMSG: new bmsg 0x7f16e1c56490 mb 0x7f16e1c56420 msg 0x7f16e1c564b0 mlen 152 dest x101 flushsz -1
2012-05-02 02:12:15.635334 : kjbmslset(0x15c91.1)) seq 0x4 reqid=0x6 (shadow 0xb48bb330.xb)(rsn 2)(mas@1)
2012-05-02 02:12:15.635355 : GSIPC:SPBMSG: send bmsg 0x7f16e1c56490 blen 184 msg 0x7f16e1c564b0 mtype 33 attr|dest x30101 bsz|fsz x1ffff
2012-05-02 02:12:15.635377 : GSIPC:SNDQ: enq msg 0x7f16e1c56490, type 65521 seq 118669, inst 1, receiver 1, queued 1

*** 2012-05-02 02:12:15.635
kclccctx: cleanup copy 0x7f16e1d94798
2012-05-02 02:12:15.635479 : [kjmpmsgi:compl][type 36][msg 0x7f16e1598588][seq 177740.0][qtime 0][ptime 1257]
2012-05-02 02:12:15.635511 : GSIPC:BSEND: flushing sndq 0xb491dd28, id 1, dcx 0xbc516778, inst 1, rcvr 1  qlen 0 1
2012-05-02 02:12:15.635536 : GSIPC:BSEND: no batch1 msg 0x7f16e1c56490 type 65521 len 184 dest (1:1)
2012-05-02 02:12:15.635557 : kjbsentscn[0x0.1ae0f1][to 1]
2012-05-02 02:12:15.635578 : GSIPC:SENDM: send msg 0x7f16e1c56490 dest x10001 seq 118669 type 65521 tkts x10002 mlen xb800e8
WAIT #0: nam='gcs remote message' ela= 180 waittime=1 poll=0 event=0 obj#=0 tim=1335939135635819
2012-05-02 02:12:15.635853 : GSIPC:RCVD: ksxp msg 0x7f16e167e0b0 sndr 1 seq 0.177741 type 32 tkts 0
2012-05-02 02:12:15.635875 : GSIPC:RCVD: watq msg 0x7f16e167e0b0 sndr 1, seq 177741, type 32, tkts 0
2012-05-02 02:12:15.636012 : GSIPC:TKT: collect msg 0x7f16e167e0b0 from 1 for rcvr -1, tickets 0
2012-05-02 02:12:15.636040 : kjbrcvdscn[0x0.1ae0f1][from 1][idx 2012-05-02 02:12:15.636060 : kjbrcvdscn[no bscn <= rscn 0x0.1ae0f1][from 1]
2012-05-02 02:12:15.636082 : GSIPC:TKT: dest (1:1) rtkt not acked 1  unassigned bufs 0  tkts 0  newbufs 0
2012-05-02 02:12:15.636102 : GSIPC:TKT: remove ctx dest (1:1)
2012-05-02 02:12:15.636125 : [kjmxmpm][type 32][seq 0.177741][msg 0x7f16e167e0b0][from 1]
2012-05-02 02:12:15.636146 : kjbmpocr(0xb0.6)seq 0x1,reqid=0x23a,(client 0x9fff7b58,0x1)(from 1)(lseq xdf0)

2????LMS????????? ??gcs remote message GSIPC ????SCN=[0x0.1ae0f0] block=1/89233???,??BAST kjbmpbast(0x15c91.1),?? block=1/89233??????? ??fairness??(?11.2.0.3???_fairness_threshold=2),?current block?KCL: F156: fairness downconvert,?Xcurrent DownConvert? Scurrent:

Instance 2:
SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0;

STATE CR_SCN_BAS
---------- ----------
2 0
3 1756658

??Instance 2 LMS ?cr block??? kjbmslset(0x15c91.1)) ????SEND QUEUE GSIPC:SNDQ: enq msg 0x7f16e1c56490?

???????Instance 1???? block: (1/89233)??? ??????:

Instance 2:

SQL> select CURRENT_RESULTS,LIGHT_WORKS from v$cr_block_server;

CURRENT_RESULTS LIGHT_WORKS
--------------- -----------
          29273         437

Instance 1 session A:

SQL>
SQL> select * from test;

        ID
----------
         2
         2

SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0;

     STATE CR_SCN_BAS
---------- ----------
         3    1761942
         3    1761932
         1          0
         3    1761520

Instance 2:

SQL> select CURRENT_RESULTS,LIGHT_WORKS from v$cr_block_server;

CURRENT_RESULTS LIGHT_WORKS
--------------- -----------
          29274         437

select * from test
END OF STMT
PARSE #140336529675592:c=0,e=337,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=1,plh=1357081020,tim=1335939668940051
EXEC #140336529675592:c=0,e=96,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=1,plh=1357081020,tim=1335939668940204
WAIT #140336529675592: nam='SQL*Net message to client' ela= 5 driver id=1650815232 #bytes=1 p3=0 obj#=0 tim=1335939668940348

*** 2012-05-02 02:21:08.940
kclscrs: req=0 block=1/89233
2012-05-02 02:21:08.940676 : kjbcro[0x15c91.1 76896.0][5]

*** 2012-05-02 02:21:08.940
kclscrs: req=0 typ=nowait-abort

*** 2012-05-02 02:21:08.940
kclscrs: bid=1:3:1:0:f:21:0:0:10:0:0:0:1:2:4:1:20:0:0:0:c3:49:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:4:3:2:1:2:0:1f:0:4d:26:a3:52:0:0:0:0:c7:c:ca:62:c3:49:0:0:0:0:1:0:17:8e:47:76:1:2:dc:5:a9:fe:17:75:0:0:0:0:0:0:0:0:0:0:0:0:99:ed:0:0:0:0:0:0:10:0:0:0
2012-05-02 02:21:08.940799 : kjbcro[0x15c91.1 76896.0][5]
2012-05-02 02:21:08.940833 : GSIPC:GMBQ: buff 0xba0ee018, queue 0xbb79a7b8, pool 0x60013fa0, freeq 0, nxt 0xbb79a7b8, prv 0xbb79a7b8
2012-05-02 02:21:08.940859 : kjbsentscn[0x0.1ae28c][to 2]
2012-05-02 02:21:08.940870 : GSIPC:SENDM: send msg 0xba0ee088 dest x20001 seq 177810 type 36 tkts xff0000 mlen x1680198
2012-05-02 02:21:08.940976 : kjbmscr(0x15c91.1)reqid=0xa(req 0xa4ff30f8)(rinst 1)hldr 2(infosz 200)(lseq x2b8)
2012-05-02 02:21:08.941314 : GSIPC:KSXPCB: msg 0xba0ee088 status 30, type 36, dest 2, rcvr 1

*** 2012-05-02 02:21:08.941
kclwcrs: wait=0 tm=707

*** 2012-05-02 02:21:08.941
kclwcrs: got 1 blocks from ksxprcv
2012-05-02 02:21:08.941818 : kjbassume[0x15c91.1][sender 2][mymode x1][myrole x0][srole x0][flgs x0][spiscn 0x0.0][swscn 0x0.0]
2012-05-02 02:21:08.941852 : kjbrcvdscn[0x0.1ae28d][from 2][idx 2012-05-02 02:21:08.941871 : kjbrcvdscn[no bscn

??????????????SCN=[0x0.1ae28c]=1761932 Version?CR block, ????receive????Xcurrent Block??SCN=1ae28d=1761933,Instance 1???Xcurrent Block???build????????SCN=1761932?CR BLOCK, ????????Current block,?????????'gc current block 2-way'?

?????????????request current block,?????kjbcro;?????Instance 2?LMS???????Current Block:

Instance 2 LMS trace:

2012-05-02 02:21:08.448743 : GSIPC:RCVD: ksxp msg 0x7f16e14a4398 sndr 1 seq 0.177810 type 36 tkts 0
2012-05-02 02:21:08.448778 : GSIPC:RCVD: watq msg 0x7f16e14a4398 sndr 1, seq 177810, type 36, tkts 0
2012-05-02 02:21:08.448798 : GSIPC:TKT: collect msg 0x7f16e14a4398 from 1 for rcvr -1, tickets 0
2012-05-02 02:21:08.448816 : kjbrcvdscn[0x0.1ae28c][from 1][idx 2012-05-02 02:21:08.448834 : kjbrcvdscn[no bscn <= rscn 0x0.1ae28c][from 1]
2012-05-02 02:21:08.448857 : GSIPC:TKT: dest (1:1) rtkt not acked 2  unassigned bufs 0  tkts 0  newbufs 0
2012-05-02 02:21:08.448875 : GSIPC:TKT: remove ctx dest (1:1)
2012-05-02 02:21:08.448970 : [kjmxmpm][type 36][seq 0.177810][msg 0x7f16e14a4398][from 1]
2012-05-02 02:21:08.448993 : kjbmpbast(0x15c91.1) reqid=0x6 (req 0xa4ff30f8)(reqinst 1)(reqid 10)(flags x0)

*** 2012-05-02 02:21:08.449
kclcrrf: req=48054 block=1/89233

*** 2012-05-02 02:21:08.449
kcl_compress_block: compressed: 6 free space: 7680
2012-05-02 02:21:08.449085 : kjbsentscn[0x0.1ae28d][to 1]
2012-05-02 02:21:08.449142 : kjbdeliver[to 1][0xa4ff30f8][10][current 1]
2012-05-02 02:21:08.449164 : kjbmssch(reqlock 0xa4ff30f8,10)(to 1)(bsz 344)
2012-05-02 02:21:08.449183 : GSIPC:AMBUF: rcv buff 0x7f16e18bcec8, pool rcvbuf, rqlen 1102

*** 2012-05-02 02:21:08.449
kclccctx: cleanup copy 0x7f16e1d94838

*** 2012-05-02 02:21:08.449
kcltouched: touch seconds 3271

*** 2012-05-02 02:21:08.449
kclgrantlk: req=48054
2012-05-02 02:21:08.449347 : [kjmpmsgi:compl][type 36][msg 0x7f16e14a4398][seq 177810.0][qtime 0][ptime 1119]
WAIT #0: nam='gcs remote message' ela= 568 waittime=1 poll=0 event=0 obj#=0 tim=1335939668449962
2012-05-02 02:21:08.450001 : GSIPC:RCVD: ksxp msg 0x7f16e1bb22a0 sndr 1 seq 0.177811 type 32 tkts 0
2012-05-02 02:21:08.450024 : GSIPC:RCVD: watq msg 0x7f16e1bb22a0 sndr 1, seq 177811, type 32, tkts 0
2012-05-02 02:21:08.450043 : GSIPC:TKT: collect msg 0x7f16e1bb22a0 from 1 for rcvr -1, tickets 0
2012-05-02 02:21:08.450060 : kjbrcvdscn[0x0.1ae28e][from 1][idx 2012-05-02 02:21:08.450078 : kjbrcvdscn[no bscn <= rscn 0x0.1ae28e][from 1]
2012-05-02 02:21:08.450097 : GSIPC:TKT: dest (1:1) rtkt not acked 3  unassigned bufs 0  tkts 0  newbufs 0
2012-05-02 02:21:08.450116 : GSIPC:TKT: remove ctx dest (1:1)
2012-05-02 02:21:08.450136 : [kjmxmpm][type 32][seq 0.177811][msg 0x7f16e1bb22a0][from 1]
2012-05-02 02:21:08.450155 : kjbmpocr(0xb0.6)seq 0x1,reqid=0x23e,(client 0x9fff7b58,0x1)(from 1)(lseq xdf4)

???Instance 2??LMS???,???build cr block,??????Instance 1?????Current Block??????Instance 2??v$cr_block_server??????LIGHT_WORKS?????current block transfer??????,??????? CR server? Light Work Rule(Light Work Rule?8i Cr Server?????????,?Remote LMS?? build CR????????,resource holder?LMS???????block,????CR build If creating the consistent read version block involves too much work (such as reading blocks from disk), then the holder sends the block to the requestor, and the requestor completes the CR fabrication. The holder maintains a fairness counter of CR requests. After the fairness threshold is reached, the holder downgrades it to lock mode.)?

??????? CR Request ????Current Block??

???:??????class?block,CR server??????? ??undo block?? undo header block?CR quest, LMS????Current Block, ????? ???? ??????? block cleanout? CR  Version???????

???????? data blocks, ??????? CR quest  & CR received?(???????Light Work Rule,LMS"??"), ??Current Block??DownConvert???S lock,??LMS???????ship??current version?block?

??????? , ?????? ,???????DownConvert?????”_fairness_threshold“???200,????Xcurrent Block?????Scurrent, ????LMS?????Current Version?Data Block:

SQL> show parameter fair

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
_fairness_threshold                  integer     200

Instance 1:

SQL>  update test set id=id+1 where id=4;

1 row updated.

Instance 2:

SQL>  update test set id=id+1 where id=2;

1 row updated.

SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0;

     STATE CR_SCN_BAS
---------- ----------
         1          0
         3    1838166

?Instance 1? ????,? ??instance 2? v$cr_block_server??

instance 1
SQL> select * from test;

        ID
----------
        10
         3

instance 2:

SQL>  select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0;

     STATE CR_SCN_BAS
---------- ----------
         1          0
         3    1883707
         8          0

SQL> select * from test;

        ID
----------
        10
         3

SQL>  select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0;

     STATE CR_SCN_BAS
---------- ----------
         1          0
         3    1883707
         8          0

...................

SQL> /

     STATE CR_SCN_BAS
---------- ----------
         2          0
         3    1883707
         3    1883695

repeat cr request on Instance 1

SQL> /

     STATE CR_SCN_BAS
---------- ----------
         8          0
         3    1883707
         3    1883695

??????_fairness_threshold????????,?????200 ????????CR serve??Downgrade?lock, ????data block? CR Request????Receive? Current Block?