在数据库trace日志中，发现有ckpt的dump，记录如下内容

*** 2019-03-05 16:29:42.977
*** SESSION ID:(1.1) 2019-03-05 16:29:42.977
*** CLIENT ID:() 2019-03-05 16:29:42.977
*** SERVICE NAME:() 2019-03-05 16:29:42.977
*** MODULE NAME:() 2019-03-05 16:29:42.977
*** ACTION NAME:() 2019-03-05 16:29:42.977

Control file enqueue hold time tracking dump at time: 793940
  1: 4370ms (rw) file: krsr.c line: 6036 count: 140720308486145 total: 4370ms time: 793059
  2: 4330ms (rw) file: krsr.c line: 3722 count: 140720308486145 total: 4330ms time: 793055

该问题可忽略且可以通过调整隐含参数关闭该trace

MOS文档中《Minact-Scn Master-Status: Grec-Scn Messages In Trace File (Doc ID 1361567.1)》记录如下

APPLIES TO:
Oracle Database - Enterprise Edition - Version 11.2.0.1 and later
Information in this document applies to any platform.
SYMPTOMS
 On 11gR2, the following messages are generated in CKPT traces:

Control file enqueue hold time tracking dump at time: 1670479
 1: 5268ms (ro) file: kcf.c line: 4726 count: 1 total: 5268ms time: 1670016
 2: 2240ms (rw) file: kct.c line: 2522 count: 1 total: 2240ms time: 1670019
 3: 941ms (ro) file: kcrr.c line: 3594 count: 1 total: 941ms time: 1670198
 4: 800ms (rw) file: kcv.c line: 15856 count: 1 total: 800ms time: 1670017
Control file enqueue hold time tracking dump at time: 1672300

CAUSE
This is an expected behavior starting with the release of 11gR2.

New controlfile enqueue hold time tracking statistics have been added in 11.2 to aid diagnosis of controlfile transaction related performance related issues:
 
Control File Enqueue AWR Statistics:
* max cf enq hold time - The maximum amount of time in milliseconds a client has held the control file enqueue.
* total cf enq hold time - The total amount of time in milliseconds all clients have held the control file enqueue.
* total number of cf enq holders - The total number of times clients have held the control file enqueue.
 
Periodically, the CKPT process dumps statistics for the top N control file enqueue holders.
N defaults to 10, but can be modified with the static hidden parameter:
_controlfile_enqueue_holding_time_tracking_size.The dump looks like the following:


Preface: "Control file enqueue hold time tracking dump at time: [relative time]".
 
* a. Time the client has held the control file enqueue.
* b. Type of client's control file enqueue transaction - rw or ro.
* c. File name where the client obtained control file enqueue.
* d. Line number where the client obtained control file enqueue.
* e. Number of times the client has held the control file enqueue since it became a member of the top N.
* f. Total time the client has held the control file in all those times from [e].
* g. Relative time the client obtained the control file enqueue from [a].


SQL> col value for a24
SQL> col description for a70
SQL> set linesize 180
SQL> select a.ksppinm name,b.ksppstvl value,a.ksppdesc description
  2    from x$ksppi a,x$ksppcv b
  3    where a.inst_id = USERENV ('Instance')
  4     and b.inst_id = USERENV ('Instance')
  5     and a.indx = b.indx
  6     and upper(a.ksppinm) LIKE upper('%&param%')
  7  order by name
  8  /


SOLUTION
 The way to shut off is set _controlfile_enqueue_holding_time_tracking_size = 0 then restart the database
 
-- spfile
alter system set "_controlfile_enqueue_holding_time_tracking_size"=0 scope=spfile;
 
-- pfile
_controlfile_enqueue_holding_time_tracking_size=0
 
Restart database