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C related, store a signed long int (32bit) as 4 octets?

- by Doori Bar

I managed to get a unsigned long int octets-representation (BE) by reading IPv4 methods, and I managed to read about how signed integers are using the MSB as the sign indicator, which makes 00 00 00 00 to be 0, while 7F FF FF FF is 2147483647. But I can't manage how to do the same for signed long integers? #include <stdio.h> #include <string.h> int main (void) { unsigned long int intu32; unsigned char octets[4]; intu32 = 255; octets[3] = (intu32) & 255; octets[2] = (intu32 >> 8) & 255; octets[1] = (intu32 >> 16) & 255; octets[0] = (intu32 >> 24) & 255; printf("(%d)(%d)(%d)(%d)\n", octets[0], octets[1], octets[2], octets[3]); intu32 = (octets[0] << 24) | (octets[1] << 16) | (octets[2] << 8) | octets[3]; printf("intu32:%lu\n", intu32); return 0; } Thanks in advance, Doori bar

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Why does C# thread die?

- by JackN

This is my 1st C# project so I may be doing something obviously improper in the code below. I am using .NET, WinForms (I think), and this is a desktop application until I get the bugs out. UpdateGui() uses Invoke((MethodInvoker)delegate to update various GUI controls based on received serial data and sends a GetStatus() command out the serial port 4 times a second. Thread Read() reads the response from serial port whenever it arrives which should be near immediate. SerialPortFixer is a SerialPort IOException Workaround in C# I found at http://zachsaw.blogspot.com/2010/07/serialport-ioexception-workaround-in-c.html. After one or both threads die I'll see something like The thread 0x1288 has exited with code 0 (0x0). in the debug code output. Why do UpdateGui() and/or Read() eventually die? public partial class UpdateStatus : Form { private readonly byte[] Command = new byte[32]; private readonly byte[] Status = new byte[32]; readonly Thread readThread; private static readonly Mutex commandMutex = new Mutex(); private static readonly Mutex statusMutex = new Mutex(); ... public UpdateStatus() { InitializeComponent(); SerialPortFixer.Execute("COM2"); if (serialPort1.IsOpen) { serialPort1.Close(); } try { serialPort1.Open(); } catch (Exception e) { labelWarning.Text = LOST_COMMUNICATIONS + e; labelStatus.Text = LOST_COMMUNICATIONS + e; labelWarning.Visible = true; } readThread = new Thread(Read); readThread.Start(); new Timer(UpdateGui, null, 0, 250); } static void ProcessStatus(byte[] status) { Status.State = (State) status[4]; Status.Speed = status[6]; // MSB Status.Speed *= 256; Status.Speed += status[5]; var Speed = Status.Speed/GEAR_RATIO; Status.Speed = (int) Speed; ... } public void Read() { while (serialPort1 != null) { try { serialPort1.Read(Status, 0, 1); if (Status[0] != StartCharacter[0]) continue; serialPort1.Read(Status, 1, 1); if (Status[1] != StartCharacter[1]) continue; serialPort1.Read(Status, 2, 1); if (Status[2] != (int)Command.GetStatus) continue; serialPort1.Read(Status, 3, 1); ... statusMutex.WaitOne(); ProcessStatus(Status); Status.update = true; statusMutex.ReleaseMutex(); } catch (Exception e) { Console.WriteLine(@"ERROR! Read() " + e); } } } public void GetStatus() { const int parameterLength = 0; // For GetStatus statusMutex.WaitOne(); Status.update = false; statusMutex.ReleaseMutex(); commandMutex.WaitOne(); if (!SendCommand(Command.GetStatus, parameterLength)) { Console.WriteLine(@"ERROR! SendCommand(GetStatus)"); } commandMutex.ReleaseMutex(); } private void UpdateGui(object x) { try { Invoke((MethodInvoker)delegate { Text = DateTime.Now.ToLongTimeString(); statusMutex.WaitOne(); if (Status.update) { if (Status.Speed > progressBarSpeed.Maximum) { Status.Speed = progressBarSpeed.Maximum; } progressBarSpeed.Value = Status.Speed; labelSpeed.Text = Status.Speed + RPM; ... } else { labelWarning.Text = LOST_COMMUNICATIONS; labelStatus.Text = LOST_COMMUNICATIONS; labelWarning.Visible = true; } statusMutex.ReleaseMutex(); GetStatus(); }); } catch (Exception e) { Console.WriteLine(@"ERROR! UpdateGui() " + e); } } }

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??Database Replay Capture????

- by Liu Maclean(???)

Database Replay?11g??????,??workload capture??????????????,???????? ??Workload Capture???????: ???????????????,???????2????,??????,???????????OLTP???????capture 10????1G???? ?????: ????????????????????? ??startup restrict????,?????????? ??capture???restrict?? ????????????? ???????????????: ??scn???????? ???????? ???????? Capture???????????workload????? ???????SYSDBA?SYSOPER????OS?? ????: ?TPCC???capture??????4.5% ????session????64KB??? ???Workload Capture?????????? ????????2?, ??RAC????workload capture file??????????????,??start_capture????? ????session????64KB???,??????????????workload capture file????Server Process??????,?????????parse???execution????,Server Process??LOGON?LOGOFF?SQL??????????PGA?,???WCR Capture PG?WCR Capture PGA?,?PGA?????????????????,Server Process???????????WCR???,?????WCR???Server Process??’WCR: capture file IO write’????? ?WCR?????????: SQL> select * from v$version; BANNER -------------------------------------------------------------------------------- Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production PL/SQL Release 11.2.0.3.0 - Production CORE 11.2.0.3.0 Production TNS for Linux: Version 11.2.0.3.0 - Production NLSRTL Version 11.2.0.3.0 - Production SQL> select name from v$event_name where name like '%WCR%'; NAME ---------------------------------------------------------------- WCR: replay client notify WCR: replay clock WCR: replay lock order WCR: replay paused WCR: RAC message context busy WCR: capture file IO write WCR: Sync context busy latch: WCR: sync latch: WCR: processes HT 11g????????WCR???LATCH 1* select name,gets from v$latch where name like '%WCR%' SQL> / NAME GETS ------------------------------ ---------- WCR: kecu cas mem 3 WCR: kecr File Count 37 WCR: MMON Create dir 1 WCR: ticker cache 0 WCR: sync 495 WCR: processes HT 0 WCR: MTS VC queue 0 7 rows selected. ????????????Database Replay Capture????? 1. ????capture dbms_workload_capture.start_capture CREATE OR REPLACE DIRECTORY dbcapture AS '/home/oracle/dbcapture'; execute dbms_workload_capture.start_capture('CAPTURE','DBCAPTURE',default_action=>'INCLUDE'); SQL> select id,name,status,start_time,end_time,connects,user_calls,dir_path from dba_workload_captures where id = (select max(id) from dba_workload_captures) ; ID ---------- NAME -------------------------------------------------------------------------------- STATUS START_TIM END_TIME CONNECTS ---------------------------------------- --------- --------- ---------- USER_CALLS ---------- DIR_PATH -------------------------------------------------------------------------------- 1 CAPTURE IN PROGRESS 08-DEC-12 11 ID ---------- NAME -------------------------------------------------------------------------------- STATUS START_TIM END_TIME CONNECTS ---------------------------------------- --------- --------- ---------- USER_CALLS ---------- DIR_PATH -------------------------------------------------------------------------------- 167 /home/oracle/dbcapture 2. ?? capture file?? [oracle@mlab2 dbcapture]$ ls -lR .: total 8 drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 cap drwxr-xr-x 3 oracle oinstall 4096 Dec 8 07:24 capfiles -rw-r--r-- 1 oracle oinstall 0 Dec 8 07:24 wcr_cap_00001.start ./cap: total 4 -rw-r--r-- 1 oracle oinstall 91 Dec 8 07:24 wcr_scapture.wmd ./capfiles: total 4 drwxr-xr-x 12 oracle oinstall 4096 Dec 8 07:24 inst1 ./capfiles/inst1: total 40 drwxr-xr-x 2 oracle oinstall 4096 Dec 8 08:31 aa drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 ab drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 ac drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 ad drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 ae drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 af drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 ag drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 ah drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 ai drwxr-xr-x 2 oracle oinstall 4096 Dec 8 07:24 aj ./capfiles/inst1/aa: total 316 -rw-r--r-- 1 oracle oinstall 1762 Dec 8 07:25 wcr_c6cdah0000001.rec -rw-r--r-- 1 oracle oinstall 16478 Dec 8 07:28 wcr_c6cf1h0000002.rec -rw-r--r-- 1 oracle oinstall 1772 Dec 8 07:29 wcr_c6cjdh0000004.rec -rw-r--r-- 1 oracle oinstall 1535 Dec 8 07:29 wcr_c6cnah0000005.rec -rw-r--r-- 1 oracle oinstall 1821 Dec 8 07:41 wcr_c6cpfh0000007.rec -rw-r--r-- 1 oracle oinstall 1815 Dec 8 07:33 wcr_c6cq6h000000a.rec -rw-r--r-- 1 oracle oinstall 1535 Dec 8 07:34 wcr_c6cxmh000000h.rec -rw-r--r-- 1 oracle oinstall 1427 Dec 8 07:41 wcr_c6cxvh000000j.rec -rw-r--r-- 1 oracle oinstall 1425 Dec 8 07:41 wcr_c6czph000000k.rec -rw-r--r-- 1 oracle oinstall 2398 Dec 8 07:49 wcr_c6dqfh000000q.rec -rw-r--r-- 1 oracle oinstall 259321 Dec 8 08:35 wcr_c6du7h000000r.rec -rw-r--r-- 1 oracle oinstall 0 Dec 8 07:55 wcr_c6f6yh000000t.rec -rw-r--r-- 1 oracle oinstall 0 Dec 8 08:28 wcr_c6h3qh0000013.rec ./capfiles/inst1/ab: total 0 ./capfiles/inst1/ac: total 0 ./capfiles/inst1/ad: total 0 ./capfiles/inst1/ae: total 0 ./capfiles/inst1/af: total 0 ./capfiles/inst1/ag: total 0 ./capfiles/inst1/ah: total 0 ./capfiles/inst1/ai: total 0 ./capfiles/inst1/aj: total 0 [oracle@mlab2 dbcapture]$ cd ./capfiles/inst1/aa [oracle@mlab2 aa]$ ls -l total 316 -rw-r--r-- 1 oracle oinstall 1762 Dec 8 07:25 wcr_c6cdah0000001.rec -rw-r--r-- 1 oracle oinstall 16478 Dec 8 07:28 wcr_c6cf1h0000002.rec -rw-r--r-- 1 oracle oinstall 1772 Dec 8 07:29 wcr_c6cjdh0000004.rec -rw-r--r-- 1 oracle oinstall 1535 Dec 8 07:29 wcr_c6cnah0000005.rec -rw-r--r-- 1 oracle oinstall 1821 Dec 8 07:41 wcr_c6cpfh0000007.rec -rw-r--r-- 1 oracle oinstall 1815 Dec 8 07:33 wcr_c6cq6h000000a.rec -rw-r--r-- 1 oracle oinstall 1535 Dec 8 07:34 wcr_c6cxmh000000h.rec -rw-r--r-- 1 oracle oinstall 1427 Dec 8 07:41 wcr_c6cxvh000000j.rec -rw-r--r-- 1 oracle oinstall 1425 Dec 8 07:41 wcr_c6czph000000k.rec -rw-r--r-- 1 oracle oinstall 2398 Dec 8 07:49 wcr_c6dqfh000000q.rec -rw-r--r-- 1 oracle oinstall 259321 Dec 8 08:35 wcr_c6du7h000000r.rec -rw-r--r-- 1 oracle oinstall 0 Dec 8 07:55 wcr_c6f6yh000000t.rec -rw-r--r-- 1 oracle oinstall 0 Dec 8 08:28 wcr_c6h3qh0000013.rec [oracle@mlab2 aa]$ ls -l |wc -l 14 ???????14??? 3. ??LOGON????Server Process [oracle@mlab2 ~]$ sqlplus / as sysdba SQL*Plus: Release 11.2.0.3.0 Production on Sat Dec 8 08:37:40 2012 Copyright (c) 1982, 2011, Oracle. All rights reserved. Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production With the Partitioning, Automatic Storage Management, OLAP, Data Mining and Real Application Testing options ?????wcr?? [oracle@mlab2 aa]$ ls -ltr total 316 -rw-r--r-- 1 oracle oinstall 1762 Dec 8 07:25 wcr_c6cdah0000001.rec -rw-r--r-- 1 oracle oinstall 16478 Dec 8 07:28 wcr_c6cf1h0000002.rec -rw-r--r-- 1 oracle oinstall 1772 Dec 8 07:29 wcr_c6cjdh0000004.rec -rw-r--r-- 1 oracle oinstall 1535 Dec 8 07:29 wcr_c6cnah0000005.rec -rw-r--r-- 1 oracle oinstall 1815 Dec 8 07:33 wcr_c6cq6h000000a.rec -rw-r--r-- 1 oracle oinstall 1535 Dec 8 07:34 wcr_c6cxmh000000h.rec -rw-r--r-- 1 oracle oinstall 1425 Dec 8 07:41 wcr_c6czph000000k.rec -rw-r--r-- 1 oracle oinstall 1427 Dec 8 07:41 wcr_c6cxvh000000j.rec -rw-r--r-- 1 oracle oinstall 1821 Dec 8 07:41 wcr_c6cpfh0000007.rec -rw-r--r-- 1 oracle oinstall 2398 Dec 8 07:49 wcr_c6dqfh000000q.rec -rw-r--r-- 1 oracle oinstall 0 Dec 8 07:55 wcr_c6f6yh000000t.rec -rw-r--r-- 1 oracle oinstall 0 Dec 8 08:28 wcr_c6h3qh0000013.rec -rw-r--r-- 1 oracle oinstall 259321 Dec 8 08:35 wcr_c6du7h000000r.rec -rw-r--r-- 1 oracle oinstall 0 Dec 8 08:37 wcr_c6hp4h0000018.rec ??????wcr_c6hp4h0000018.rec ??? SQL> select spid from v$process where addr = ( select paddr from v$session where sid=(select distinct sid from v$mystat)); SPID ------------------------ 14293 ????????????????14293, ???????????????,??????wcr_c6hp4h0000018.rec [oracle@mlab2 ~]$ ls -l /proc/14293/fd total 0 lr-x------ 1 oracle oinstall 64 Dec 8 08:39 0 -> /dev/null l-wx------ 1 oracle oinstall 64 Dec 8 08:39 1 -> /dev/null lrwx------ 1 oracle oinstall 64 Dec 8 08:39 10 -> /u01/app/oracle/product/11201/db_1/rdbms/audit/CRMV_ora_14293_1.aud l-wx------ 1 oracle oinstall 64 Dec 8 08:39 11 -> /u01/app/oracle/diag/rdbms/crmv/CRMV/trace/CRMV_ora_14293.trc l-wx------ 1 oracle oinstall 64 Dec 8 08:39 12 -> pipe:[34585895] l-wx------ 1 oracle oinstall 64 Dec 8 08:39 13 -> /u01/app/oracle/diag/rdbms/crmv/CRMV/trace/CRMV_ora_14293.trm l-wx------ 1 oracle oinstall 64 Dec 8 08:39 2 -> /dev/null lr-x------ 1 oracle oinstall 64 Dec 8 08:39 3 -> /dev/null lr-x------ 1 oracle oinstall 64 Dec 8 08:39 4 -> /dev/null lr-x------ 1 oracle oinstall 64 Dec 8 08:39 5 -> /u01/app/oracle/product/11201/db_1/rdbms/mesg/oraus.msb lr-x------ 1 oracle oinstall 64 Dec 8 08:39 6 -> /proc/14293/fd lr-x------ 1 oracle oinstall 64 Dec 8 08:39 7 -> /dev/zero lrwx------ 1 oracle oinstall 64 Dec 8 08:39 8 -> /home/oracle/dbcapture/capfiles/inst1/aa/wcr_c6hp4h0000018.rec lr-x------ 1 oracle oinstall 64 Dec 8 08:39 9 -> pipe:[34585894] ?????lsof?? [root@mlab2 ~]# lsof|grep wcr_c6hp4h0000018.rec oracle 14293 oracle 8u REG 8,1 0 17629644 /home/oracle/dbcapture/capfiles/inst1/aa/wcr_c6hp4h0000018.rec ????????,??Server Process????WCR REC??,?Server Process LOGON?????? 3.????SQL??: SQL> select 1 from dual; 1 ---------- 1 SQL> / 1 ---------- 1 [oracle@mlab2 aa]$ strings wcr_c6hp4h0000018.rec ==»????SQL????, ??????? ??????SQL???,???????????????WCR??????,LOGON???????????SQL????,????????? [oracle@mlab2 aa]$ strings wcr_c6hp4h0000018.rec 11.2.0.3.0 *File header info. (Shadow process='14293') D0576B5D710A34F4E043B201A8C0ECFE SYS; NLS_LANGUAGE? AMERICAN> NLS_TERRITORY? AMERICA> NLS_CURRENCY? NLS_ISO_CURRENCY? AMERICA> NLS_NUMERIC_CHARACTERS? NLS_CALENDAR? GREGORIAN> NLS_DATE_FORMAT? DD-MON-RR> NLS_DATE_LANGUAGE? AMERICAN> NLS_CHARACTERSET? AL32UTF8> NLS_SORT? BINARY> NLS_TIME_FORMAT? HH.MI.SSXFF AM> NLS_TIMESTAMP_FORMAT? DD-MON-RR HH.MI.SSXFF AM> NLS_TIME_TZ_FORMAT? HH.MI.SSXFF AM TZR> NLS_TIMESTAMP_TZ_FORMAT? DD-MON-RR HH.MI.SSXFF AM TZR> NLS_DUAL_CURRENCY? NLS_SPECIAL_CHARS? NLS_NCHAR_CHARACTERSET? UTF8> NLS_COMP? BINARY> NLS_LENGTH_SEMANTICS? BYTE> NLS_NCHAR_CONV_EXCP? FALSE (DESCRIPTION=(ADDRESS=(PROTOCOL=beq)(PROGRAM=/u01/app/oracle/product/11201/db_1/bin/oracle)(ARGV0=oracleCRMV)(ARGS='(DESCRIPTION=(LOCAL=YES)(ADDRESS=(PROTOCOL=beq)))')(DETACH=NO))(CONNECT_DATA=(CID=(PROGRAM=sqlplus)(HOST=mlab2.oracle.com)(USER=oracle)))) ,[email protected] (TNS V1-V3)U tselect spid from v$process where addr = ( select paddr from v$session where sid=(select distinct sid from v$mystat)) ` _ select 1 from dual select 1 from dual ??????????????????? [oracle@mlab2 aa]$ strings wcr_c6hp4h0000018.rec 9`9_^B create table vva(t1 int) `:_i :`:_iB `;_^ ;`;_^B create table vva(t1 int) `_i >`>_iB FusC `?_^ ?`?_^B FvWC _begin for i in 1..50000 loop execute immediate 'select 1 from dual where 2='||i; end loop; end; ?SERVER PROCESS LOGOFF ??????? C`E_ B k^2C ????Server Process????parse?execution???WCR??,??????????PGA?,????????????,????????,?????WCR???????????,???????? 4. ?????? SQL> oradebug setmypid Statement processed. SQL> oradebug dump processstate 10; Statement processed. SQL> oradebug tracefile_name /u01/app/oracle/diag/rdbms/crmv/CRMV/trace/CRMV_ora_14293.trc ?processstate ??????????????? WCR: capture file IO write,??Server process??WCR ?? 3: waited for 'SQL*Net message to client' driver id=0x62657100, #bytes=0x1, =0x0 wait_id=139 seq_num=140 snap_id=1 wait times: snap=0.000007 sec, exc=0.000007 sec, total=0.000007 sec wait times: max=infinite wait counts: calls=0 os=0 occurred after 0.934091 sec of elapsed time 4: waited for 'latch: shared pool' address=0x60106b20, number=0x133, tries=0x0 wait_id=138 seq_num=139 snap_id=1 wait times: snap=0.000066 sec, exc=0.000066 sec, total=0.000066 sec wait times: max=infinite wait counts: calls=0 os=0 occurred after 1.180690 sec of elapsed time 5: waited for 'WCR: capture file IO write' =0x0, =0x0, =0x0 wait_id=137 seq_num=138 snap_id=1 wait times: snap=0.000189 sec, exc=0.000189 sec, total=0.000189 sec wait times: max=infinite wait counts: calls=0 os=0 occurred after 3.122783 sec of elapsed time 6: waited for 'WCR: capture file IO write' =0x0, =0x0, =0x0 wait_id=136 seq_num=137 snap_id=1 wait times: snap=0.000191 sec, exc=0.000191 sec, total=0.000191 sec wait times: max=infinite wait counts: calls=0 os=0 occurred after 3.053132 sec of elapsed time 7: waited for 'WCR: capture file IO write' 5.??PGA???? SQL> oradebug dump heapdump 536870917; Statement processed. grep WCR /u01/app/oracle/diag/rdbms/crmv/CRMV/trace/CRMV_ora_14293.trc Chunk 7fb1b606bfc0 sz= 65600 freeable "WCR Capture PG " ds=0x7fb1b6115f90 Chunk 7fb1b6111e18 sz= 4224 freeable "WCR Capture PG " ds=0x7fb1b6115f90 Chunk 7fb1b6112e98 sz= 4184 freeable "WCR Capture PG " ds=0x7fb1b6115f90 Chunk 7fb1b6113ef0 sz= 4224 freeable "WCR Capture PG " ds=0x7fb1b6115f90 Chunk 7fb1b6114f70 sz= 4104 recreate "WCR Capture PG " latch=(nil) Chunk 7fb1b6115f78 sz= 160 freeable "WCR Capture PGA" Chunk 7fb1b6116018 sz= 3248 freeable "WCR Capture PGA" Subheap ds=0x7fb1b6115f90 heap name= WCR Capture PG size= 82336 HEAP DUMP heap name="WCR Capture PG" desc=0x7fb1b6115f90 FIVE LARGEST SUB HEAPS for heap name="WCR Capture PG" desc=0x7fb1b6115f9 PGA???WCR Capture PG ?WCR Capture PGA?freeable or recreate??chunk,???????Server Process???OS Chunk 7fb1b606bfc0 sz= 65600 freeable "WCR Capture PG " ds=0x7fb1b6115f90 sz= 65600=» 64k ??????????64k??,???????????????64k WCR????????????:)! 6.???? ??WCR CAPTURE????????2? SQL> SELECT x.ksppinm NAME, y.ksppstvl VALUE, x.ksppdesc describ 2 FROM SYS.x$ksppi x, SYS.x$ksppcv y 3 WHERE x.inst_id = USERENV ('Instance') 4 AND y.inst_id = USERENV ('Instance') 5 AND x.indx = y.indx 6 AND x.ksppinm in ('_capture_buffer_size','_wcr_control'); NAME VALUE DESCRIB -------------------- -------------------- ------------------------------------------------------------ _wcr_control 0 Oracle internal test WCR parameter used ONLY for testing! _capture_buffer_size 65536 To set the size of the PGA I/O recording buffers ??_capture_buffer_size ??PGA?WCR BUFFER?SIZE,???64k _wcr_control ??WCR?????,?????? ????,??????: 1. ???WCR WORKLOAD CAPTURE???????????,??Server Process????(????)2. ???server process????WCR??3. Server Proess???LOGON?LOGOFF?SQL?????????WCR???4. Server Process????????Immediate mode,????????PGA?(WCR Capture) subheap?,??????????????(timeout?????)5. ????, Server Process????????Immediate mode,?capture????parse??execution??(?????capture???parse?????????????,parse????capture???),?????LOGON?SQL??(???????)??PGA?WCR Capture?????,???????,????????,??tpcc??????4.5%6. ????_capture_buffer_size ??PGA?WCR BUFFER?SIZE,???64k7. WCR Capture?????binrary 2????,?????,????????????????WCR capture file8. WCR: capture file IO write?????Server Process??WCR??

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