alert 檔案中的資訊：insert pending collecting tran, scn=1009024904 (hex=0.3c247f

在alter_SID.log檔案中發現的資訊，我們的客戶端程式呼叫A資料庫的Procedure , 其中會有database link 連線到B資料庫（應該屬於分散式資料庫系統吧），從資訊中看不到是否是網路斷開還是系統問題，因為沒有作任何動作， 程式出現異常。重新開啟程式就正常了。
一般什麼情況下出現這種現象 ？ 什麼情況下系統會鎖住操作的表而必須強制回滾？？

Sat Feb 21 13:43:56 2004
ARC0: Beginning to archive log# 24 seq# 31516
ARC0: Completed archiving log# 24 seq# 31516
Sat Feb 21 13:58:02 2004
Thread 1 advanced to log sequence 31518
  Current log# 18 seq# 31518 mem# 0: /u01/redo32a.log
  Current log# 18 seq# 31518 mem# 1: /u06/redo32b.log
Sat Feb 21 13:58:02 2004
ARC0: Beginning to archive log# 17 seq# 31517
ARC0: Completed archiving log# 17 seq# 31517
Sat Feb 21 14:12:13 2004
alter tablespace log_index add datafile '/u05/log_index6.dbf' size 2025m
Sat Feb 21 14:12:46 2004
Error 3113 trapped in 2PC on transaction 31.46.788239. Cleaning up.
Sat Feb 21 14:13:08 2004
Error 3113 trapped in 2PC on transaction 36.27.788358. Cleaning up.
Sat Feb 21 14:13:14 2004
Error 3113 trapped in 2PC on transaction 32.17.788340. Cleaning up.
Sat Feb 21 14:13:16 2004
Error 3113 trapped in 2PC on transaction 32.1.788302. Cleaning up.
Sat Feb 21 14:13:19 2004
Error 3113 trapped in 2PC on transaction 31.38.788118. Cleaning up.
Sat Feb 21 14:13:25 2004
Error stack returned to user:  

Sat Feb 21 14:13:19 2004
Error 3113 trapped in 2PC on transaction 31.38.788118. Cleaning up.
Sat Feb 21 14:13:25 2004
Error stack returned to user:
ORA-02050: 交易 36.27.788358 被倒回, 有些遠端 DB 可能有問題
Sat Feb 21 14:13:25 2004
Error stack returned to user:
Sat Feb 21 14:13:25 2004
Error stack returned to user:
Sat Feb 21 14:13:25 2004
Error stack returned to user:
ORA-03113: 通訊通道上出現 EOF
ORA-02050: 交易 32.1.788302 被倒回, 有些遠端 DB 可能有問題
ORA-02050: 交易 31.46.788239 被倒回, 有些遠端 DB 可能有問題
ORA-02050: 交易 32.17.788340 被倒回, 有些遠端 DB 可能有問題
ORA-03113: 通訊通道上出現 EOF
ORA-03113: 通訊通道上出現 EOF
ORA-03113: 通訊通道上出現 EOF
Sat Feb 21 14:13:25 2004
DISTRIB TRAN INTEL.38bccc85.36.27.788358
  is local tran 36.27.788358 (hex=24.1b.c0786)

ORA-02050: 交易 32.1.788302 被倒回, 有些遠端 DB 可能有問題
ORA-02050: 交易 31.46.788239 被倒回, 有些遠端 DB 可能有問題
ORA-02050: 交易 32.17.788340 被倒回, 有些遠端 DB 可能有問題
ORA-03113: 通訊通道上出現 EOF
ORA-03113: 通訊通道上出現 EOF
ORA-03113: 通訊通道上出現 EOF
Sat Feb 21 14:13:25 2004
DISTRIB TRAN INTEL.38bccc85.36.27.788358
  is local tran 36.27.788358 (hex=24.1b.c0786)
  insert pending collecting tran, scn=1009024882 (hex=0.3c247f72)
Sat Feb 21 14:13:25 2004
Error stack returned to user:
ORA-02050: 交易 31.38.788118 被倒回, 有些遠端 DB 可能有問題
ORA-03113: 通訊通道上出現 EOF
Sat Feb 21 14:13:25 2004
DISTRIB TRAN INTEL.38bccc85.36.27.788358
  is local tran 36.27.788358 (hex=24.1b.c0786))
  delete pending collecting tran, scn=1009024882 (hex=0.3c247f72)
Sat Feb 21 14:13:26 2004
Completed: alter tablespace log_index add datafile '/u05/log_
Sat Feb 21 14:13:28 2004
Thread 1 advanced to log sequence 31519
  Current log# 19 seq# 31519 mem# 0: /u01/redo33a.log

Sat Feb 21 14:14:36 2004
ARC0: Beginning to archive log# 20 seq# 31520
ARC0: Completed archiving log# 20 seq# 31520
Sat Feb 21 14:14:37 2004
Thread 1 advanced to log sequence 31522
  Current log# 22 seq# 31522 mem# 0: /u01/redo36a.log
  Current log# 22 seq# 31522 mem# 1: /u06/redo36b.log
Sat Feb 21 14:14:37 2004
ARC0: Beginning to archive log# 21 seq# 31521
ARC0: Completed archiving log# 21 seq# 31521
Sat Feb 21 14:18:33 2004

Sat Feb 21 14:14:37 2004
ARC0: Beginning to archive log# 21 seq# 31521
ARC0: Completed archiving log# 21 seq# 31521
Sat Feb 21 14:18:33 2004
DISTRIB TRAN INTEL.38bccc85.31.38.788118
  is local tran 31.38.788118 (hex=1f.26.c0696)
  insert pending collecting tran, scn=1009024904 (hex=0.3c247f88)
DISTRIB TRAN INTEL.38bccc85.31.46.788239
  is local tran 31.46.788239 (hex=1f.2e.c070f)
  insert pending collecting tran, scn=1009024878 (hex=0.3c247f6e)
DISTRIB TRAN INTEL.38bccc85.32.1.788302
  is local tran 32.1.788302 (hex=20.01.c074e)
  insert pending collecting tran, scn=1009024885 (hex=0.3c247f75)
DISTRIB TRAN INTEL.38bccc85.32.17.788340
  is local tran 32.17.788340 (hex=20.11.c0774)
  insert pending collecting tran, scn=1009024884 (hex=0.3c247f74)
Sat Feb 21 14:18:33 2004
DISTRIB TRAN INTEL.38bccc85.31.38.788118
  is local tran 31.38.788118 (hex=1f.26.c0696))
  delete pending collecting tran, scn=1009024904 (hex=0.3c247f88)
DISTRIB TRAN INTEL.38bccc85.31.46.788239
  is local tran 31.46.788239 (hex=1f.2e.c070f))
  delete pending collecting tran, scn=1009024878 (hex=0.3c247f6e)
DISTRIB TRAN INTEL.38bccc85.32.1.788302

DISTRIB TRAN INTEL.38bccc85.32.17.788340
  is local tran 32.17.788340 (hex=20.11.c0774))
  delete pending collecting tran, scn=1009024884 (hex=0.3c247f74)
Sat Feb 21 14:29:21 2004
Thread 1 advanced to log sequence 31523
  Current log# 23 seq# 31523 mem# 0: /u01/redo37a.log
  Current log# 23 seq# 31523 mem# 1: /u06/redo37b.log
Sat Feb 21 14:29:21 2004
ARC0: Beginning to archive log# 22 seq# 31522
ARC0: Completed archiving log# 22 seq# 31522
Sat Feb 21 14:29:33 2004
Thread 1 advanced to log sequence 31524
  Current log# 24 seq# 31524 mem# 0: /u01/redo38a.log
  Current log# 24 seq# 31524 mem# 1: /u06/redo38b.log

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