0322理解db file parallel read等待事件2

简介: [20180322]理解db file parallel read等待事件2.txt --//上个星期的学习:http://blog.itpub.net/267265/viewspace-2151973/ https://docs.

[20180322]理解db file parallel read等待事件2.txt

--//上个星期的学习:http://blog.itpub.net/267265/viewspace-2151973/

https://docs.oracle.com/cd/E11882_01/server.112/e40402/waitevents003.htm#REFRN00531

db file parallel read

This happens during recovery. It can also happen during buffer prefetching, as an optimization (rather than performing
multiple single-block reads). Database blocks that need to be changed as part of recovery are read in parallel from the
database.

Wait Time: Wait until all of the I/Os are completed
------------------------------------------------------------------------------------------------
Parameter     Description
------------------------------------------------------------------------------------------------
files         This indicates the number of files to which the session is reading
blocks        This indicates the total number of blocks to be read
requests      This indicates the total number of I/O requests, which will be the same as blocks

--//我看了生产系统,查询不到select * from V$ACTIVE_SESSION_HISTORY where event='db file parallel read'.相关等待事件.
--//偶然,我发现动态取样会出现这样的等待事件做一个验证:

1.环境
SCOTT@book> @ ver1
PORT_STRING                    VERSION        BANNER
------------------------------ -------------- --------------------------------------------------------------------------------
x86_64/Linux 2.4.xx            11.2.0.4.0     Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production

SCOTT@book> create table t as select rownum id from dual connect by level<=2;
Table created.

SCOTT@book> ALTER TABLE t MINIMIZE RECORDS_PER_BLOCK ;
Table altered.
--//这样可以实现每块2条记录.

SCOTT@book> insert into t select rownum+2 from dual connect by level <=8e4-2;
79998 rows created.

SCOTT@book> commit ;
Commit complete.
--// 注表太小可能不会出现'db file parallel read'.

2.测试:
SCOTT@book> alter system flush buffer_cache;

System altered.

SCOTT@book> @ &r/10046on 12

Session altered.

SCOTT@book> select count(*) from t;
  COUNT(*)
----------
     80000

SCOTT@book> @ &r/dpc '' ''
PLAN_TABLE_OUTPUT
-------------------------------------
SQL_ID  cyzznbykb509s, child number 0
-------------------------------------
select count(*) from t
Plan hash value: 2966233522

----------------------------------------------------------------------------------------------------------------------
| Id  | Operation          | Name | Starts | E-Rows | Cost (%CPU)| E-Time   | A-Rows |   A-Time   | Buffers | Reads  |
----------------------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT   |      |      1 |        | 11033 (100)|          |      1 |00:00:00.25 |   77758 |  40173 |
|   1 |  SORT AGGREGATE    |      |      1 |      1 |            |          |      1 |00:00:00.25 |   77758 |  40173 |
|   2 |   TABLE ACCESS FULL| T    |      1 |  82692 | 11033   (1)| 00:02:13 |  80000 |00:00:00.39 |   77758 |  40173 |
----------------------------------------------------------------------------------------------------------------------
Query Block Name / Object Alias (identified by operation id):
-------------------------------------------------------------
   1 - SEL$1
   2 - SEL$1 / T@SEL$1

Note
-----
   - dynamic sampling used for this statement (level=2)

24 rows selected.

SCOTT@book> @ &r/10046off
Session altered.


3.检查转储:
=====================
PARSING IN CURSOR #140324703611992 len=417 dep=1 uid=83 oct=3 lid=83 tim=1521769053615495 hv=3915441694 ad='7da3be08' sqlid='7brx71bnq1thy'
SELECT /* OPT_DYN_SAMP */ /*+ ALL_ROWS IGNORE_WHERE_CLAUSE NO_PARALLEL(SAMPLESUB) opt_param('parallel_execution_enabled', 'false') NO_PARALLEL_INDEX(SAMPLESUB) NO_SQL_TUNE */ NVL(SUM(C1),:"SYS_B_0"), NVL(SUM(C2),:"SYS_B_1") FROM (SELECT /*+ NO_PARALLEL("T") FULL("T") NO_
END OF STMT
PARSE #140324703611992:c=0,e=615,p=0,cr=0,cu=0,mis=1,r=0,dep=1,og=1,plh=0,tim=1521769053615492
=====================

EXEC #140324703611992:c=2000,e=2101,p=1,cr=2,cu=0,mis=1,r=0,dep=1,og=1,plh=1807638002,tim=1521769053617698
WAIT #140324703611992: nam='db file sequential read' ela= 13 file#=4 block#=546 blocks=1 obj#=90538 tim=1521769053617758
WAIT #140324703611992: nam='db file sequential read' ela= 12 file#=4 block#=768 blocks=1 obj#=90538 tim=1521769053617878
WAIT #140324703611992: nam='db file sequential read' ela= 9 file#=4 block#=545 blocks=1 obj#=90538 tim=1521769053617928
WAIT #140324703611992: nam='db file parallel read' ela= 870 files=1 blocks=127 requests=127 obj#=90538 tim=1521769053619309
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
WAIT #140324703611992: nam='db file sequential read' ela= 12 file#=4 block#=786 blocks=1 obj#=90538 tim=1521769053619554
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=1214 blocks=1 obj#=90538 tim=1521769053619677
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=3303 blocks=1 obj#=90538 tim=1521769053619834
WAIT #140324703611992: nam='db file sequential read' ela= 11 file#=4 block#=3636 blocks=1 obj#=90538 tim=1521769053619911
WAIT #140324703611992: nam='db file sequential read' ela= 9 file#=4 block#=3897 blocks=1 obj#=90538 tim=1521769053619968
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=4478 blocks=1 obj#=90538 tim=1521769053620062
WAIT #140324703611992: nam='db file sequential read' ela= 11 file#=4 block#=5223 blocks=1 obj#=90538 tim=1521769053620176
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=5640 blocks=1 obj#=90538 tim=1521769053620240
WAIT #140324703611992: nam='db file sequential read' ela= 9 file#=4 block#=6258 blocks=1 obj#=90538 tim=1521769053620318
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=6418 blocks=1 obj#=90538 tim=1521769053620389
WAIT #140324703611992: nam='db file sequential read' ela= 11 file#=4 block#=6726 blocks=1 obj#=90538 tim=1521769053620476
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=7180 blocks=1 obj#=90538 tim=1521769053620572
WAIT #140324703611992: nam='db file sequential read' ela= 9 file#=4 block#=7270 blocks=1 obj#=90538 tim=1521769053620643
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=7513 blocks=1 obj#=90538 tim=1521769053620730
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=8556 blocks=1 obj#=90538 tim=1521769053620848
WAIT #140324703611992: nam='db file parallel read' ela= 852 files=1 blocks=125 requests=125 obj#=90538 tim=1521769053622175
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
WAIT #140324703611992: nam='db file scattered read' ela= 42 file#=4 block#=11009 blocks=8 obj#=90538 tim=1521769053622523
WAIT #140324703611992: nam='db file sequential read' ela= 11 file#=4 block#=11071 blocks=1 obj#=90538 tim=1521769053622632
WAIT #140324703611992: nam='db file scattered read' ela= 28 file#=4 block#=11310 blocks=8 obj#=90538 tim=1521769053622759
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=11425 blocks=1 obj#=90538 tim=1521769053622873
WAIT #140324703611992: nam='db file sequential read' ela= 21 file#=4 block#=13010 blocks=1 obj#=90538 tim=1521769053623007
...
WAIT #140324703611992: nam='db file sequential read' ela= 10 file#=4 block#=41830 blocks=1 obj#=90538 tim=1521769053627728
FETCH #140324703611992:c=9999,e=10077,p=388,cr=384,cu=1,mis=0,r=1,dep=1,og=1,plh=1807638002,tim=1521769053627803
STAT #140324703611992 id=1 cnt=1 pid=0 pos=1 obj=0 op='SORT AGGREGATE (cr=384 pr=388 pw=0 time=10075 us)'
STAT #140324703611992 id=2 cnt=128 pid=1 pos=1 obj=90538 op='TABLE ACCESS SAMPLE T (cr=384 pr=388 pw=0 time=1911 us cost=2 size=12 card=1)'
CLOSE #140324703611992:c=0,e=8,dep=1,type=0,tim=1521769053627961
=====================

--//可以发现出现'db file parallel read'.

$ grep "^WAIT #140324703611992: nam='db file " /u01/app/oracle/diag/rdbms/book/book/trace/book_ora_38623.trc | sed 's/^.*blocks=//g'| cut -f1 -d' '| xargs echo | sed 's/ /+/g'|bc -l
388

SCOTT@book> select OWNER,SEGMENT_NAME,SEGMENT_TYPE,HEADER_FILE,HEADER_BLOCK,BYTES,BLOCKS from dba_segments where owner=user and segment_name='T';
OWNER  SEGMENT_NAME         SEGMENT_TYPE       HEADER_FILE HEADER_BLOCK      BYTES     BLOCKS
------ -------------------- ------------------ ----------- ------------ ---------- ----------
SCOTT  T                    TABLE                        4          546  335544320      40960

SCOTT@book> show parameter optimizer_dynamic_sampling
NAME                       TYPE    VALUE
-------------------------- ------- -----
optimizer_dynamic_sampling integer 2

--//有点奇怪的是,执行如下没有显示:
select * from V$ACTIVE_SESSION_HISTORY where event='db file parallel read';
select * from V$ACTIVE_SESSION_HISTORY where sql_id='7brx71bnq1thy';

4.重新使用strace跟踪看看:
--//重新建立表开始略.不知道为什么如果不这样做以后刷新后在执行根本不需要db file parallel read.
SCOTT@book> alter system flush buffer_cache;
System altered.

SCOTT@book> @ &r/spid
       SID    SERIAL# PROCESS                  SERVER    SPID       PID  P_SERIAL# C50
---------- ---------- ------------------------ --------- ------ ------- ---------- --------------------------------------------------
       274          7 38865                    DEDICATED 38866       21          4 alter system kill session '274,7' immediate;

SCOTT@book> show parameter filesystemio_options
NAME                 TYPE   VALUE
-------------------- ------ -----
filesystemio_options string NONE

--//注:不使用异步IO,主要是strace的跟踪异步io有点不会看.

$ strace -f -p 38866 -o /tmp/aa3.txt
Process 38866 attached - interrupt to quit

SCOTT@book> @ &r/10046on 12

Session altered.

SCOTT@book> select count(*) from t;
  COUNT(*)
----------
     80000

SCOTT@book> @ &r/10046off
Session altered.

$ strace -f -p 38866 -o /tmp/aa.txt
Process 38866 attached - interrupt to quit
^CProcess 38866 detached


WAIT #140334076535760: nam='db file sequential read' ela= 130 file#=4 block#=546 blocks=1 obj#=90540 tim=1521770828837576
WAIT #140334076535760: nam='db file sequential read' ela= 117 file#=4 block#=768 blocks=1 obj#=90540 tim=1521770828837966
WAIT #140334076535760: nam='db file sequential read' ela= 107 file#=4 block#=545 blocks=1 obj#=90540 tim=1521770828838464
WAIT #140334076535760: nam='db file parallel read' ela= 12239 files=1 blocks=127 requests=127 obj#=90540 tim=1521770828851403
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
WAIT #140334076535760: nam='db file sequential read' ela= 118 file#=4 block#=786 blocks=1 obj#=90540 tim=1521770828852240
WAIT #140334076535760: nam='db file sequential read' ela= 112 file#=3 block#=160 blocks=1 obj#=0 tim=1521770828852567
WAIT #140334076535760: nam='db file sequential read' ela= 114 file#=4 block#=1214 blocks=1 obj#=90540 tim=1521770828853324
WAIT #140334076535760: nam='db file sequential read' ela= 110 file#=4 block#=3303 blocks=1 obj#=90540 tim=1521770828853923
...
WAIT #140334076535760: nam='db file sequential read' ela= 113 file#=4 block#=8556 blocks=1 obj#=90540 tim=1521770828860805
WAIT #140334076535760: nam='db file parallel read' ela= 12060 files=1 blocks=125 requests=125 obj#=90540 tim=1521770828873808
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
WAIT #140334076535760: nam='db file scattered read' ela= 180 file#=4 block#=11009 blocks=8 obj#=90540 tim=1521770828874623
WAIT #140334076535760: nam='db file sequential read' ela= 109 file#=4 block#=11071 blocks=1 obj#=90540 tim=1521770828875334
....
WAIT #140334076535760: nam='db file scattered read' ela= 158 file#=4 block#=38001 blocks=8 obj#=90540 tim=1521770828902991
WAIT #140334076535760: nam='db file sequential read' ela= 110 file#=4 block#=38113 blocks=1 obj#=90540 tim=1521770828903877
WAIT #140334076535760: nam='db file sequential read' ela= 109 file#=4 block#=40427 blocks=1 obj#=90540 tim=1521770828904472
WAIT #140334076535760: nam='db file sequential read' ela= 110 file#=4 block#=41306 blocks=1 obj#=90540 tim=1521770828905165
FETCH #140334076535760:c=23996,e=68611,p=389,cr=385,cu=1,mis=0,r=1,dep=1,og=1,plh=1807638002,tim=1521770828905938
STAT #140334076535760 id=1 cnt=1 pid=0 pos=1 obj=0 op='SORT AGGREGATE (cr=385 pr=389 pw=0 time=68518 us)'
STAT #140334076535760 id=2 cnt=128 pid=1 pos=1 obj=90540 op='TABLE ACCESS SAMPLE T (cr=385 pr=389 pw=0 time=68325 us cost=2 size=12 card=1)'
CLOSE #140334076535760:c=0,e=114,dep=1,type=0,tim=1521770828906977
=====================


$ grep -n  '38866 pread(257' /tmp/aa3.txt
36:38866 pread(257, "#\242\0\0\"\2\0\1.\254d\27\3\0\2\4:\313\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 4472832) = 8192
--//注意行号,WAIT #140334076535760应该从这里开始.
213:38866 pread(257, "#\242\0\0\"\2\0\1.\254d\27\3\0\2\4:\313\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 4472832) = 8192
216:38866 pread(257, " \242\0\0\0\3\0\1\234\250d\27\3\0\f\4\265L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 6291456) = 8192
221:38866 pread(257, "!\242\0\0!\2\0\1/\254d\27\3\0\1\4j\323\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 4464640) = 8192
--//以上3个单块读.

224:38866 pread(257, " \242\0\0\1\3\0\1\235\250d\27\3\0\2\4\367L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 6299648) = 8192
225:38866 pread(257, " \242\0\0\200\3\0\1\235\250d\27\3\0B\4\267L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 7340032) = 8192
226:38866 pread(257, " \242\0\0\201\3\0\1\236\250d\27\3\0\2\4\365L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 7348224) = 8192
227:38866 pread(257, " \242\0\0\0\4\0\1\262\250d\27\3\0\n\4\261L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 8388608) = 8192
228:38866 pread(257, " \242\0\0\1\4\0\1\263\250d\27\3\0\2\4\363L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 8396800) = 8192
229:38866 pread(257, " \242\0\0\200\4\0\1\311\250d\27\3\0\24\4\263L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 9437184) = 8192
230:38866 pread(257, " \242\0\0\201\4\0\1\316\250d\27\3\0\2\4\361L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 9445376) = 8192
231:38866 pread(257, " \242\0\0\0\5\0\1\354\250d\27\3\0\27\4\255L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 10485760) = 8192
232:38866 pread(257, " \242\0\0\1\5\0\1\355\250d\27\3\0\2\4\357L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 10493952) = 8192
233:38866 pread(257, " \242\0\0\200\5\0\1\23\251d\27\3\0\1\4\257L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 11534336) = 8192
234:38866 pread(257, " \242\0\0\201\5\0\1\26\251d\27\3\0\2\4\355L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 11542528) = 8192
235:38866 pread(257, " \242\0\0\0\6\0\1.\251d\27\3\0\1\4\251L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 12582912) = 8192
236:38866 pread(257, " \242\0\0\1\6\0\1/\251d\27\3\0\2\4\353L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 12591104) = 8192
237:38866 pread(257, " \242\0\0\200\6\0\1g\251d\27\3\0\5\4\253L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 13631488) = 8192
238:38866 pread(257, " \242\0\0\201\6\0\1j\251d\27\3\0\2\4\351L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 13639680) = 8192
239:38866 pread(257, " \242\0\0\0\7\0\1\217\251d\27\3\0\1\4\245L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 14680064) = 8192
240:38866 pread(257, " \242\0\0\1\7\0\1\221\251d\27\3\0\2\4\347L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 14688256) = 8192
241:38866 pread(257, " \242\0\0\200\7\0\1\265\251d\27\3\0\2\4\247L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 15728640) = 8192
242:38866 pread(257, " \242\0\0\201\7\0\1\270\251d\27\3\0\2\4\345L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 15736832) = 8192
243:38866 pread(257, " \242\0\0\0\10\0\1\322\251d\27\3\0\25\4\241L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 16777216) = 8192
244:38866 pread(257, " \242\0\0\1\10\0\1\325\251d\27\3\0\2\4\343L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 16785408) = 8192
245:38866 pread(257, " \242\0\0\0\t\0\1\5\252d\27\3\0\2\4\243L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 18874368) = 8192
246:38866 pread(257, " \242\0\0\1\t\0\1\10\252d\27\3\0\2\4\341L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 18882560) = 8192
247:38866 pread(257, " \242\0\0\0\n\0\0016\252d\27\3\0\2\4\235L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 20971520) = 8192
248:38866 pread(257, " \242\0\0\1\n\0\1;\252d\27\3\0\2\4\337L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 20979712) = 8192
249:38866 pread(257, " \242\0\0\200\n\0\1u\252d\27\3\0\1\4\237L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 22020096) = 8192
250:38866 pread(257, " \242\0\0\201\n\0\1x\252d\27\3\0\2\4\335L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 22028288) = 8192
251:38866 pread(257, " \242\0\0\0\v\0\1\270\252d\27\3\0\2\4\231L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 23068672) = 8192
252:38866 pread(257, " \242\0\0\1\v\0\1\273\252d\27\3\0\2\4\333L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 23076864) = 8192
253:38866 pread(257, " \242\0\0\200\v\0\1\34\253d\27\3\0\1\4\233L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 24117248) = 8192
254:38866 pread(257, " \242\0\0\201\v\0\1$\253d\27\3\0\2\4\331L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 24125440) = 8192
255:38866 pread(257, " \242\0\0\0\f\0\1\\\253d\27\3\0>\4\225L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 25165824) = 8192
256:38866 pread(257, " \242\0\0\1\f\0\1]\253d\27\3\0\2\4\327L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 25174016) = 8192
257:38866 pread(257, " \242\0\0\200\f\0\1]\253d\27\3\0B\4\227L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 26214400) = 8192
258:38866 pread(257, " \242\0\0\201\f\0\1^\253d\27\3\0\2\4\325L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 26222592) = 8192
259:38866 pread(257, " \242\0\0\0\r\0\1^\253d\27\3\0B\4\221L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 27262976) = 8192
260:38866 pread(257, " \242\0\0\1\r\0\1_\253d\27\3\0\2\4\323L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 27271168) = 8192
261:38866 pread(257, " \242\0\0\0\16\0\1_\253d\27\3\0B\4\223L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 29360128) = 8192
262:38866 pread(257, " \242\0\0\1\16\0\1`\253d\27\3\0\2\4\321L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 29368320) = 8192
263:38866 pread(257, " \242\0\0\200\16\0\1`\253d\27\3\0B\4\215L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 30408704) = 8192
264:38866 pread(257, " \242\0\0\201\16\0\1a\253d\27\3\0\2\4\317L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 30416896) = 8192
265:38866 pread(257, " \242\0\0\0\17\0\1a\253d\27\3\0B\4\217L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 31457280) = 8192
266:38866 pread(257, " \242\0\0\1\17\0\1b\253d\27\3\0\2\4\315L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 31465472) = 8192
267:38866 pread(257, " \242\0\0\200\17\0\1b\253d\27\3\0B\4\211L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 32505856) = 8192
268:38866 pread(257, " \242\0\0\201\17\0\1c\253d\27\3\0\2\4\313L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 32514048) = 8192
269:38866 pread(257, " \242\0\0\0\20\0\1c\253d\27\3\0B\4\213L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 33554432) = 8192
270:38866 pread(257, " \242\0\0\1\20\0\1d\253d\27\3\0\2\4\311L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 33562624) = 8192
271:38866 pread(257, " \242\0\0\200\20\0\1d\253d\27\3\0B\4\205L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 34603008) = 8192
272:38866 pread(257, " \242\0\0\201\20\0\1e\253d\27\3\0\2\4\307L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 34611200) = 8192
273:38866 pread(257, " \242\0\0\0\21\0\1e\253d\27\3\0B\4\207L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 35651584) = 8192
274:38866 pread(257, " \242\0\0\1\21\0\1f\253d\27\3\0\2\4\305L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 35659776) = 8192
275:38866 pread(257, " \242\0\0\200\21\0\1f\253d\27\3\0B\4\201L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 36700160) = 8192
276:38866 pread(257, " \242\0\0\201\21\0\1g\253d\27\3\0\2\4\303L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 36708352) = 8192
277:38866 pread(257, " \242\0\0\0\22\0\1g\253d\27\3\0B\4\203L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 37748736) = 8192
278:38866 pread(257, " \242\0\0\1\22\0\1h\253d\27\3\0\2\4\301L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 37756928) = 8192
279:38866 pread(257, " \242\0\0\200\22\0\1h\253d\27\3\0B\4\375L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 38797312) = 8192
280:38866 pread(257, " \242\0\0\201\22\0\1i\253d\27\3\0\2\4\277L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 38805504) = 8192
281:38866 pread(257, " \242\0\0\0\23\0\1i\253d\27\3\0B\4\377L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 39845888) = 8192
282:38866 pread(257, " \242\0\0\1\23\0\1j\253d\27\3\0\2\4\275L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 39854080) = 8192
283:38866 pread(257, " \242\0\0\200\23\0\1j\253d\27\3\0B\4\371L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 40894464) = 8192
284:38866 pread(257, " \242\0\0\201\23\0\1k\253d\27\3\0\2\4\273L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 40902656) = 8192
285:38866 pread(257, " \242\0\0\0\24\0\1k\253d\27\3\0B\4\373L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 41943040) = 8192
286:38866 pread(257, " \242\0\0\1\24\0\1l\253d\27\3\0\2\4\271L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 41951232) = 8192
287:38866 pread(257, " \242\0\0\200\24\0\1l\253d\27\3\0B\4\365L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 42991616) = 8192
288:38866 pread(257, " \242\0\0\201\24\0\1m\253d\27\3\0\2\4\267L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 42999808) = 8192
289:38866 pread(257, " \242\0\0\0\25\0\1m\253d\27\3\0B\4\367L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 44040192) = 8192
290:38866 pread(257, " \242\0\0\1\25\0\1n\253d\27\3\0\2\4\265L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 44048384) = 8192
291:38866 pread(257, " \242\0\0\200\25\0\1n\253d\27\3\0B\4\361L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 45088768) = 8192
292:38866 pread(257, " \242\0\0\201\25\0\1p\253d\27\3\0\2\4\263L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 45096960) = 8192
293:38866 pread(257, " \242\0\0\0\26\0\1p\253d\27\3\0B\4\363L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 46137344) = 8192
294:38866 pread(257, " \242\0\0\1\26\0\1q\253d\27\3\0\2\4\261L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 46145536) = 8192
295:38866 pread(257, " \242\0\0\200\26\0\1q\253d\27\3\0B\4\355L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 47185920) = 8192
296:38866 pread(257, " \242\0\0\201\26\0\1r\253d\27\3\0\2\4\257L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 47194112) = 8192
297:38866 pread(257, " \242\0\0\0\27\0\1r\253d\27\3\0B\4\357L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 48234496) = 8192
298:38866 pread(257, " \242\0\0\1\27\0\1s\253d\27\3\0\2\4\255L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 48242688) = 8192
299:38866 pread(257, " \242\0\0\200\27\0\1s\253d\27\3\0B\4\351L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 49283072) = 8192
300:38866 pread(257, " \242\0\0\201\27\0\1t\253d\27\3\0\2\4\253L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 49291264) = 8192
301:38866 pread(257, " \242\0\0\0\30\0\1t\253d\27\3\0B\4\353L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 50331648) = 8192
302:38866 pread(257, " \242\0\0\1\30\0\1u\253d\27\3\0\2\4\251L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 50339840) = 8192
303:38866 pread(257, " \242\0\0\200\30\0\1u\253d\27\3\0B\4\345L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 51380224) = 8192
304:38866 pread(257, " \242\0\0\201\30\0\1v\253d\27\3\0\2\4\247L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 51388416) = 8192
305:38866 pread(257, " \242\0\0\0\31\0\1v\253d\27\3\0B\4\347L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 52428800) = 8192
306:38866 pread(257, " \242\0\0\1\31\0\1w\253d\27\3\0\2\4\245L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 52436992) = 8192
307:38866 pread(257, " \242\0\0\200\31\0\1w\253d\27\3\0B\4\341L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 53477376) = 8192
308:38866 pread(257, " \242\0\0\201\31\0\1x\253d\27\3\0\2\4\243L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 53485568) = 8192
309:38866 pread(257, " \242\0\0\0\32\0\1x\253d\27\3\0B\4\343L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 54525952) = 8192
310:38866 pread(257, " \242\0\0\1\32\0\1y\253d\27\3\0\2\4\241L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 54534144) = 8192
311:38866 pread(257, " \242\0\0\200\32\0\1y\253d\27\3\0B\4\335L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 55574528) = 8192
312:38866 pread(257, " \242\0\0\201\32\0\1z\253d\27\3\0\2\4\237L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 55582720) = 8192
313:38866 pread(257, " \242\0\0\0\33\0\1z\253d\27\3\0B\4\337L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 56623104) = 8192
314:38866 pread(257, " \242\0\0\1\33\0\1{\253d\27\3\0\2\4\235L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 56631296) = 8192
315:38866 pread(257, " \242\0\0\200\33\0\1{\253d\27\3\0B\4\331L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 57671680) = 8192
316:38866 pread(257, " \242\0\0\201\33\0\1|\253d\27\3\0\2\4\233L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 57679872) = 8192
317:38866 pread(257, " \242\0\0\0\34\0\1|\253d\27\3\0B\4\333L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 58720256) = 8192
318:38866 pread(257, " \242\0\0\1\34\0\1}\253d\27\3\0\2\4\231L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 58728448) = 8192
319:38866 pread(257, " \242\0\0\200\34\0\1}\253d\27\3\0B\4\325L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 59768832) = 8192
320:38866 pread(257, " \242\0\0\201\34\0\1~\253d\27\3\0\2\4\227L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 59777024) = 8192
321:38866 pread(257, " \242\0\0\0\35\0\1~\253d\27\3\0B\4\327L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 60817408) = 8192
322:38866 pread(257, " \242\0\0\1\35\0\1\177\253d\27\3\0\2\4\225L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 60825600) = 8192
323:38866 pread(257, " \242\0\0\200\35\0\1\177\253d\27\3\0B\4\321L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 61865984) = 8192
324:38866 pread(257, " \242\0\0\201\35\0\1\200\253d\27\3\0\2\4\223L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 61874176) = 8192
325:38866 pread(257, " \242\0\0\0\36\0\1\200\253d\27\3\0B\4\323L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 62914560) = 8192
326:38866 pread(257, " \242\0\0\1\36\0\1\201\253d\27\3\0\2\4\221L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 62922752) = 8192
327:38866 pread(257, " \242\0\0\200\36\0\1\201\253d\27\3\0B\4\315L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 63963136) = 8192
328:38866 pread(257, " \242\0\0\201\36\0\1\202\253d\27\3\0\2\4\217L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 63971328) = 8192
329:38866 pread(257, " \242\0\0\0\37\0\1\203\253d\27\3\0B\4\317L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 65011712) = 8192
330:38866 pread(257, " \242\0\0\1\37\0\1\204\253d\27\3\0\2\4\215L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 65019904) = 8192
331:38866 pread(257, " \242\0\0\200\37\0\1\204\253d\27\3\0B\4\311L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 66060288) = 8192
332:38866 pread(257, " \242\0\0\201\37\0\1\205\253d\27\3\0\2\4\213L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 66068480) = 8192
333:38866 pread(257, " \242\0\0\0 \0\1\205\253d\27\3\0B\4\313L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 67108864) = 8192
334:38866 pread(257, " \242\0\0\1 \0\1\206\253d\27\3\0\2\4\211L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 67117056) = 8192
335:38866 pread(257, " \242\0\0\200 \0\1\206\253d\27\3\0B\4\305L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 68157440) = 8192
336:38866 pread(257, " \242\0\0\201 \0\1\207\253d\27\3\0\2\4\207L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 68165632) = 8192
337:38866 pread(257, " \242\0\0\0!\0\1\207\253d\27\3\0B\4\307L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 69206016) = 8192
338:38866 pread(257, " \242\0\0\1!\0\1\210\253d\27\3\0\2\4\205L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 69214208) = 8192
339:38866 pread(257, " \242\0\0\200!\0\1\210\253d\27\3\0B\4\301L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 70254592) = 8192
340:38866 pread(257, " \242\0\0\201!\0\1\211\253d\27\3\0\2\4\203L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 70262784) = 8192
341:38866 pread(257, " \242\0\0\0\"\0\1\211\253d\27\3\0B\4\303L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 71303168) = 8192
342:38866 pread(257, " \242\0\0\1\"\0\1\212\253d\27\3\0\2\4\201L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 71311360) = 8192
343:38866 pread(257, " \242\0\0\200\"\0\1\212\253d\27\3\0B\4=L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 72351744) = 8192
344:38866 pread(257, " \242\0\0\201\"\0\1\213\253d\27\3\0\2\4\177L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 72359936) = 8192
345:38866 pread(257, " \242\0\0\0#\0\1\213\253d\27\3\0B\4?L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 73400320) = 8192
346:38866 pread(257, " \242\0\0\1#\0\1\214\253d\27\3\0\2\4}L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 73408512) = 8192
347:38866 pread(257, " \242\0\0\200#\0\1\215\253d\27\3\0\2\4\372L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 74448896) = 8192
348:38866 pread(257, " \242\0\0\0$\0\1\217\253d\27\3\0\17\4~M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 75497472) = 8192
349:38866 pread(257, " \242\0\0\1$\0\1\216\253d\27\3\0\23\4xL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 75505664) = 8192
350:38866 pread(257, " \242\0\0\2$\0\1\221\253d\27\3\0\20\4zO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 75513856) = 8192
--//以上127块.对应'db file parallel read',你可以发现offset不断变大.
357:38866 pread(257, "\6\242\0\0\22\3\0\1\232\250d\27\3\0\3\4\30\314\0\0\1\0\0\0\254a\1\0\232\250d\27"..., 8192, 6438912) = 8192
367:38866 pread(257, "\6\242\0\0\276\4\0\1\311\250d\27\3\0\1\4\234\302\0\0\1\0\2\0\254a\1\0\276\250d\27"..., 8192, 9945088) = 8192
372:38866 pread(257, "\6\242\0\0\347\f\0\1]\253d\27\3\0\3\4&v\0\0\1\0\23\0\254a\1\0]\253d\27"..., 8192, 27058176) = 8192
379:38866 pread(257, "\6\242\0\0004\16\0\1_\253d\27\3\0\3\4do\0\0\1\0\17\0\254a\1\0_\253d\27"..., 8192, 29786112) = 8192
386:38866 pread(257, "\6\242\0\0009\17\0\0011\254d\27\3\0\1\6\277\215\0\0\1\316@\0\254a\1\0a\253d\27"..., 8192, 31924224) = 8192
389:38866 pread(257, "\6\242\0\0~\21\0\0011\254d\27\3\0\1\6\211\6\0\0\1\0\0\0\254a\1\0e\253d\27"..., 8192, 36683776) = 8192
394:38866 pread(257, "\6\242\0\0g\24\0\0011\254d\27\3\0\1\6u\266\0\0\1\0\26\0\254a\1\0k\253d\27"..., 8192, 42786816) = 8192
397:38866 pread(257, "\6\242\0\0\10\26\0\0011\254d\27\3\0\1\6[\277\0\0\1\0\0\0\254a\1\0p\253d\27"..., 8192, 46202880) = 8192
400:38866 pread(257, "\6\242\0\0r\30\0\1t\253d\27\3\0\3\4O\234\0\0\1\0\0\0\254a\1\0t\253d\27"..., 8192, 51265536) = 8192
407:38866 pread(257, "\6\242\0\0\22\31\0\1v\253d\27\3\0\3\4\355\362\0\0\1\0\26\0\254a\1\0v\253d\27"..., 8192, 52576256) = 8192
414:38866 pread(257, "\6\242\0\0F\32\0\1x\253d\27\3\0\3\4'\311\0\0\1\0\0\0\254a\1\0x\253d\27"..., 8192, 55099392) = 8192
419:38866 pread(257, "\6\242\0\0\f\34\0\1|\253d\27\3\0\3\4\315`\0\0\1\0\0\0\254a\1\0|\253d\27"..., 8192, 58818560) = 8192
426:38866 pread(257, "\6\242\0\0f\34\0\1|\253d\27\3\0\3\4\205\307\0\0\1\22@\0\254a\1\0|\253d\27"..., 8192, 59555840) = 8192
431:38866 pread(257, "\6\242\0\0Y\35\0\1~\253d\27\3\0\3\4\364\372\0\0\1\0\31\0\254a\1\0~\253d\27"..., 8192, 61546496) = 8192
438:38866 pread(257, "\6\242\0\0l!\0\1\207\253d\27\3\0\3\4o{\0\0\1\0\t\0\254a\1\0\207\253d\27"..., 8192, 70090752) = 8192
445:38866 pread(257, " \242\0\0\3$\0\1\222\253d\27\3\0\2\4tN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 75522048) = 8192
446:38866 pread(257, " \242\0\0\0(\0\1\224\253d\27\3\0\17\4rM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 83886080) = 8192
447:38866 pread(257, " \242\0\0\1(\0\1\223\253d\27\3\0\227\4tL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 83894272) = 8192
448:38866 pread(257, " \242\0\0\2(\0\1\226\253d\27\3\0\20\4vO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 83902464) = 8192
449:38866 pread(257, " \242\0\0\3(\0\1\227\253d\27\3\0\2\4pN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 83910656) = 8192
450:38866 pread(257, " \242\0\0\0,\0\1\231\253d\27\3\0\17\4vM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 92274688) = 8192
451:38866 pread(257, " \242\0\0\1,\0\1\230\253d\27\3\0\23\4pL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 92282880) = 8192
452:38866 pread(257, " \242\0\0\2,\0\1\233\253d\27\3\0\20\4rO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 92291072) = 8192
453:38866 pread(257, " \242\0\0\3,\0\1\234\253d\27\3\0\2\4lN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 92299264) = 8192
454:38866 pread(257, " \242\0\0\0000\0\1\236\253d\27\3\0\17\4jM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 100663296) = 8192
455:38866 pread(257, " \242\0\0\0010\0\1\235\253d\27\3\0\23\4lL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 100671488) = 8192
456:38866 pread(257, " \242\0\0\0020\0\1\241\253d\27\3\0\20\4nO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 100679680) = 8192
457:38866 pread(257, " \242\0\0\0030\0\1\242\253d\27\3\0\2\4hN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 100687872) = 8192
458:38866 pread(257, " \242\0\0\0004\0\1\244\253d\27\3\0\17\4nM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 109051904) = 8192
459:38866 pread(257, " \242\0\0\0014\0\1\243\253d\27\3\0\23\4hL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 109060096) = 8192
460:38866 pread(257, " \242\0\0\0024\0\1\246\253d\27\3\0\20\4jO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 109068288) = 8192
461:38866 pread(257, " \242\0\0\0034\0\1\247\253d\27\3\0\2\4dN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 109076480) = 8192
462:38866 pread(257, " \242\0\0\0008\0\1\251\253d\27\3\0\17\4bM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 117440512) = 8192
463:38866 pread(257, " \242\0\0\0018\0\1\250\253d\27\3\0\23\4dL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 117448704) = 8192
464:38866 pread(257, " \242\0\0\0028\0\1\253\253d\27\3\0\226\4fO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 117456896) = 8192
465:38866 pread(257, " \242\0\0\0038\0\1\254\253d\27\3\0\2\4`N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 117465088) = 8192
466:38866 pread(257, " \242\0\0\0<\0\1\256\253d\27\3\0\17\4fM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 125829120) = 8192
467:38866 pread(257, " \242\0\0\1<\0\1\255\253d\27\3\0\23\4`L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 125837312) = 8192
468:38866 pread(257, " \242\0\0\2<\0\1\260\253d\27\3\0\20\4bO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 125845504) = 8192
469:38866 pread(257, " \242\0\0\3<\0\1\261\253d\27\3\0\2\4\\N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 125853696) = 8192
470:38866 pread(257, " \242\0\0\0@\0\1\263\253d\27\3\0\17\4ZM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 134217728) = 8192
471:38866 pread(257, " \242\0\0\1@\0\1\262\253d\27\3\0\23\4\\L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 134225920) = 8192
472:38866 pread(257, " \242\0\0\2@\0\1\265\253d\27\3\0\20\4^O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 134234112) = 8192
473:38866 pread(257, " \242\0\0\3@\0\1\266\253d\27\3\0\2\4XN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 134242304) = 8192
474:38866 pread(257, " \242\0\0\0D\0\1\271\253d\27\3\0\17\4^M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 142606336) = 8192
475:38866 pread(257, " \242\0\0\1D\0\1\270\253d\27\3\0\4\4XL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 142614528) = 8192
476:38866 pread(257, " \242\0\0\2D\0\1\273\253d\27\3\0\20\4ZO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 142622720) = 8192
477:38866 pread(257, " \242\0\0\3D\0\1\274\253d\27\3\0\2\4TN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 142630912) = 8192
478:38866 pread(257, " \242\0\0\0H\0\1\276\253d\27\3\0\17\4RM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 150994944) = 8192
479:38866 pread(257, " \242\0\0\1H\0\1\275\253d\27\3\0\23\4TL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 151003136) = 8192
480:38866 pread(257, " \242\0\0\2H\0\1\300\253d\27\3\0\20\4VO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 151011328) = 8192
481:38866 pread(257, " \242\0\0\3H\0\1\301\253d\27\3\0\2\4PN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 151019520) = 8192
482:38866 pread(257, " \242\0\0\0L\0\1\303\253d\27\3\0\17\4VM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 159383552) = 8192
483:38866 pread(257, " \242\0\0\1L\0\1\302\253d\27\3\0\23\4PL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 159391744) = 8192
484:38866 pread(257, " \242\0\0\2L\0\1\305\253d\27\3\0\20\4RO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 159399936) = 8192
485:38866 pread(257, " \242\0\0\3L\0\1\306\253d\27\3\0\2\4LN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 159408128) = 8192
486:38866 pread(257, " \242\0\0\0P\0\1\310\253d\27\3\0\17\4JM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 167772160) = 8192
487:38866 pread(257, " \242\0\0\1P\0\1\307\253d\27\3\0\23\4LL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 167780352) = 8192
488:38866 pread(257, " \242\0\0\2P\0\1\312\253d\27\3\0\20\4NO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 167788544) = 8192
489:38866 pread(257, " \242\0\0\3P\0\1\313\253d\27\3\0\2\4HN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 167796736) = 8192
490:38866 pread(257, " \242\0\0\0T\0\1\315\253d\27\3\0\17\4NM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 176160768) = 8192
491:38866 pread(257, " \242\0\0\1T\0\1\314\253d\27\3\0\23\4HL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 176168960) = 8192
492:38866 pread(257, " \242\0\0\2T\0\1\320\253d\27\3\0\4\4JO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 176177152) = 8192
493:38866 pread(257, " \242\0\0\3T\0\1\321\253d\27\3\0\2\4DN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 176185344) = 8192
494:38866 pread(257, " \242\0\0\0X\0\1\323\253d\27\3\0\17\4BM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 184549376) = 8192
495:38866 pread(257, " \242\0\0\1X\0\1\322\253d\27\3\0\23\4DL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 184557568) = 8192
496:38866 pread(257, " \242\0\0\2X\0\1\325\253d\27\3\0\20\4FO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 184565760) = 8192
497:38866 pread(257, " \242\0\0\3X\0\1\326\253d\27\3\0\2\4@N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 184573952) = 8192
498:38866 pread(257, " \242\0\0\0\\\0\1\330\253d\27\3\0\17\4FM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 192937984) = 8192
499:38866 pread(257, " \242\0\0\1\\\0\1\327\253d\27\3\0\23\4@L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 192946176) = 8192
500:38866 pread(257, " \242\0\0\2\\\0\1\332\253d\27\3\0\20\4BO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 192954368) = 8192
501:38866 pread(257, " \242\0\0\3\\\0\1\333\253d\27\3\0\2\4<N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 192962560) = 8192
502:38866 pread(257, " \242\0\0\0`\0\1\336\253d\27\3\0\255\4:M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 201326592) = 8192
503:38866 pread(257, " \242\0\0\1`\0\1\334\253d\27\3\0\23\4<L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 201334784) = 8192
504:38866 pread(257, " \242\0\0\2`\0\1\340\253d\27\3\0\20\4>O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 201342976) = 8192
505:38866 pread(257, " \242\0\0\3`\0\1\341\253d\27\3\0\2\0048N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 201351168) = 8192
506:38866 pread(257, " \242\0\0\0d\0\1\343\253d\27\3\0\17\4>M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 209715200) = 8192
507:38866 pread(257, " \242\0\0\1d\0\1\342\253d\27\3\0\23\0048L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 209723392) = 8192
508:38866 pread(257, " \242\0\0\2d\0\1\345\253d\27\3\0\20\4:O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 209731584) = 8192
509:38866 pread(257, " \242\0\0\3d\0\1\346\253d\27\3\0\2\0044N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 209739776) = 8192
510:38866 pread(257, " \242\0\0\0h\0\1\350\253d\27\3\0\17\0042M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 218103808) = 8192
511:38866 pread(257, " \242\0\0\1h\0\1\347\253d\27\3\0\23\0044L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 218112000) = 8192
512:38866 pread(257, " \242\0\0\2h\0\1\353\253d\27\3\0\20\0046O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 218120192) = 8192
513:38866 pread(257, " \242\0\0\3h\0\1\354\253d\27\3\0\2\0040N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 218128384) = 8192
514:38866 pread(257, " \242\0\0\0l\0\1\356\253d\27\3\0\17\0046M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 226492416) = 8192
515:38866 pread(257, " \242\0\0\1l\0\1\355\253d\27\3\0\23\0040L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 226500608) = 8192
516:38866 pread(257, " \242\0\0\2l\0\1\360\253d\27\3\0\20\0042O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 226508800) = 8192
517:38866 pread(257, " \242\0\0\3l\0\1\361\253d\27\3\0\2\4,N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 226516992) = 8192
518:38866 pread(257, " \242\0\0\0p\0\1\363\253d\27\3\0\17\4*M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 234881024) = 8192
519:38866 pread(257, " \242\0\0\1p\0\1\362\253d\27\3\0\23\4,L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 234889216) = 8192
520:38866 pread(257, " \242\0\0\2p\0\1\365\253d\27\3\0\20\4.O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 234897408) = 8192
521:38866 pread(257, " \242\0\0\3p\0\1\366\253d\27\3\0\2\4(N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 234905600) = 8192
522:38866 pread(257, " \242\0\0\0t\0\1\370\253d\27\3\0\17\4.M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 243269632) = 8192
523:38866 pread(257, " \242\0\0\1t\0\1\367\253d\27\3\0\273\4(L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 243277824) = 8192
524:38866 pread(257, " \242\0\0\2t\0\1\372\253d\27\3\0\20\4*O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 243286016) = 8192
525:38866 pread(257, " \242\0\0\3t\0\1\373\253d\27\3\0\2\4$N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 243294208) = 8192
526:38866 pread(257, " \242\0\0\0x\0\1\375\253d\27\3\0\17\4\"M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 251658240) = 8192
527:38866 pread(257, " \242\0\0\1x\0\1\374\253d\27\3\0\23\4$L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 251666432) = 8192
528:38866 pread(257, " \242\0\0\2x\0\1\377\253d\27\3\0\20\4&O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 251674624) = 8192
529:38866 pread(257, " \242\0\0\3x\0\1\0\254d\27\3\0\2\4 N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 251682816) = 8192
530:38866 pread(257, " \242\0\0\0|\0\1\2\254d\27\3\0\31\4&M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 260046848) = 8192
531:38866 pread(257, " \242\0\0\1|\0\1\1\254d\27\3\0\23\4 L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 260055040) = 8192
532:38866 pread(257, " \242\0\0\2|\0\1\4\254d\27\3\0\20\4\"O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 260063232) = 8192
533:38866 pread(257, " \242\0\0\3|\0\1\5\254d\27\3\0\2\4\34N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 260071424) = 8192
534:38866 pread(257, " \242\0\0\0\200\0\1\7\254d\27\3\0\17\4\32M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 268435456) = 8192
535:38866 pread(257, " \242\0\0\1\200\0\1\6\254d\27\3\0\23\4\34L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 268443648) = 8192
536:38866 pread(257, " \242\0\0\2\200\0\1\t\254d\27\3\0\20\4\36O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 268451840) = 8192
537:38866 pread(257, " \242\0\0\3\200\0\1\n\254d\27\3\0\2\4\30N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 268460032) = 8192
538:38866 pread(257, " \242\0\0\0\204\0\1\f\254d\27\3\0\17\4\36M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 276824064) = 8192
539:38866 pread(257, " \242\0\0\1\204\0\1\v\254d\27\3\0\23\4\30L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 276832256) = 8192
540:38866 pread(257, " \242\0\0\2\204\0\1\16\254d\27\3\0\272\4\32O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 276840448) = 8192
541:38866 pread(257, " \242\0\0\3\204\0\1\17\254d\27\3\0\2\4\24N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 276848640) = 8192
542:38866 pread(257, " \242\0\0\0\210\0\1\21\254d\27\3\0\17\4\22M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 285212672) = 8192
543:38866 pread(257, " \242\0\0\1\210\0\1\20\254d\27\3\0\23\4\24L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 285220864) = 8192
544:38866 pread(257, " \242\0\0\2\210\0\1\23\254d\27\3\0\20\4\26O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 285229056) = 8192
545:38866 pread(257, " \242\0\0\3\210\0\1\24\254d\27\3\0\2\4\20N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 285237248) = 8192
546:38866 pread(257, " \242\0\0\0\214\0\1\26\254d\27\3\0\17\4\26M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 293601280) = 8192
547:38866 pread(257, " \242\0\0\1\214\0\1\25\254d\27\3\0\23\4\20L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 293609472) = 8192
548:38866 pread(257, " \242\0\0\2\214\0\1\30\254d\27\3\0\20\4\22O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 293617664) = 8192
549:38866 pread(257, " \242\0\0\3\214\0\1\31\254d\27\3\0\2\4\fN\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 293625856) = 8192
550:38866 pread(257, " \242\0\0\0\220\0\1\33\254d\27\3\0\17\4\nM\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 301989888) = 8192
551:38866 pread(257, " \242\0\0\1\220\0\1\32\254d\27\3\0&\4\fL\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 301998080) = 8192
552:38866 pread(257, " \242\0\0\2\220\0\1\35\254d\27\3\0\20\4\16O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 302006272) = 8192
553:38866 pread(257, " \242\0\0\3\220\0\1\36\254d\27\3\0\2\4\10N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 302014464) = 8192
554:38866 pread(257, " \242\0\0\0\224\0\1 \254d\27\3\0\17\4\16M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 310378496) = 8192
555:38866 pread(257, " \242\0\0\1\224\0\1\37\254d\27\3\0\23\4\10L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 310386688) = 8192
556:38866 pread(257, " \242\0\0\2\224\0\1#\254d\27\3\0\240\4\nO\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 310394880) = 8192
557:38866 pread(257, " \242\0\0\3\224\0\1$\254d\27\3\0\2\4\4N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 310403072) = 8192
558:38866 pread(257, " \242\0\0\0\230\0\1&\254d\27\3\0\17\4\2M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 318767104) = 8192
559:38866 pread(257, " \242\0\0\1\230\0\1%\254d\27\3\0\23\4\4L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 318775296) = 8192
560:38866 pread(257, " \242\0\0\2\230\0\1(\254d\27\3\0\20\4\6O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 318783488) = 8192
561:38866 pread(257, " \242\0\0\3\230\0\1)\254d\27\3\0\2\4\0N\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 318791680) = 8192
562:38866 pread(257, " \242\0\0\0\234\0\1+\254d\27\3\0\17\4\6M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 327155712) = 8192
563:38866 pread(257, " \242\0\0\1\234\0\1*\254d\27\3\0\23\4\0L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 327163904) = 8192
564:38866 pread(257, " \242\0\0\2\234\0\1-\254d\27\3\0\20\4\2O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 327172096) = 8192
565:38866 pread(257, " \242\0\0\3\234\0\1.\254d\27\3\0\2\4\374O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 327180288) = 8192
566:38866 pread(257, " \242\0\0\0\240\0\1/\254d\27\3\0P\4\6\t\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 335544320) = 8192
567:38866 pread(257, " \242\0\0\1\240\0\1/\254d\27\3\0\336\4\374M\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 335552512) = 8192
568:38866 pread(257, " \242\0\0\2\240\0\1/\254d\27\3\0\1\4\36O\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 335560704) = 8192
569:38866 pread(257, " \242\0\0\3\240\0\1.\254d\27\3\0\2\4\345u\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 335568896) = 8192
574:38866 pread(257, "\6\242\0\0\1+\0\1\224\253d\27\3\0\3\4\300}\0\0\1\0\10\0\254a\1\0\224\253d\27"..., 65536, 90185728) = 65536
581:38866 pread(257, "\6\242\0\0?+\0\1\224\253d\27\3\0\3\4\201Q\0\0\1\0\v\0\254a\1\0\224\253d\27"..., 8192, 90693632) = 8192
588:38866 pread(257, "\6\242\0\0.,\0\1\230\253d\27\3\0\3\4\200\207\0\0\1\0\0\0\254a\1\0\230\253d\27"..., 65536, 92651520) = 65536
593:38866 pread(257, "\6\242\0\0\241,\0\1\230\253d\27\3\0\3\4E\377\0\0\1\0\0\0\254a\1\0\230\253d\27"..., 8192, 93593600) = 8192
600:38866 pread(257, "\6\242\0\0\3222\0\1\240\253d\27\3\0\3\4n\34\0\0\1\0\0\0\254a\1\0\240\253d\27"..., 8192, 106577920) = 8192
607:38866 pread(257, "\6\242\0\0y3\0\1\237\253d\27\3\0\3\4\370\36\0\0\1\f@\0\254a\1\0\237\253d\27"..., 8192, 107945984) = 8192
612:38866 pread(257, "\6\242\0\0\3134\0\1\243\253d\27\3\0\3\4\266\345\0\0\1\316@\0\254a\1\0\243\253d\27"..., 8192, 110714880) = 8192
619:38866 pread(257, "\6\242\0\0\0245\0\1\243\253d\27\3\0\1\4\227Q\0\0\1\3\30\34\254a\1\0\242\253d\27"..., 8192, 111312896) = 8192
624:38866 pread(257, "\6\242\0\0\0317\0\1\244\253d\27\3\0\1\4\345\227\0\0\1\0\16\0\254a\1\0\242\253d\27"..., 8192, 115548160) = 8192
631:38866 pread(257, "\6\242\0\0\3738\0\1\250\253d\27\3\0\3\4Y\31\0\0\1\0\3\0\254a\1\0\250\253d\27"..., 8192, 119496704) = 8192
638:38866 pread(257, "\6\242\0\0\3069\0\1\247\253d\27\3\0\3\0044\246\0\0\1\0\0\0\254a\1\0\247\253d\27"..., 8192, 121159680) = 8192
643:38866 pread(257, "\6\242\0\0\340>\0\1\257\253d\27\3\0\3\4(\317\0\0\1\0\36\0\254a\1\0\257\253d\27"..., 8192, 131858432) = 8192
650:38866 pread(257, "\6\242\0\0\16?\0\1\256\253d\27\3\0\3\4V\314\0\0\1\0\0\0\254a\1\0\256\253d\27"..., 8192, 132235264) = 8192
655:38866 pread(257, "\6\242\0\0PA\0\1\261\253d\27\3\0\3\4\307\17\0\0\1\f@\0\254a\1\0\261\253d\27"..., 8192, 136970240) = 8192
662:38866 pread(257, "\6\242\0\0\306B\0\1\264\253d\27\3\0\3\4\37\317\0\0\1\0\0\0\254a\1\0\264\253d\27"..., 8192, 140034048) = 8192
669:38866 pread(257, "\6\242\0\0xC\0\1\263\253d\27\3\0\3\4\2418\0\0\1\0\0\0\254a\1\0\263\253d\27"..., 8192, 141492224) = 8192
674:38866 pread(257, "\6\242\0\0EH\0\1\275\253d\27\3\0\3\0048\377\0\0\1\0\0\0\254a\1\0\275\253d\27"..., 65536, 151560192) = 65536
681:38866 pread(257, "\6\242\0\0~H\0\1\275\253d\27\3\0\3\4!\207\0\0\1\0\0\0\254a\1\0\275\253d\27"..., 8192, 152027136) = 8192
688:38866 pread(257, "\6\242\0\0\231J\0\1\277\253d\27\3\0\3\4\262\234\0\0\1\0\0\0\254a\1\0\277\253d\27"..., 8192, 156442624) = 8192
693:38866 pread(257, "\6\242\0\0\376Q\0\1\306\253d\27\3\0\3\4lE\0\0\1\0\0\0\254a\1\0\306\253d\27"..., 8192, 171950080) = 8192
700:38866 pread(257, "\6\242\0\0\372T\0\1\314\253d\27\3\0\3\4\330\374\0\0\1\0\0\0\254a\1\0\314\253d\27"..., 8192, 178208768) = 8192
705:38866 pread(257, "\6\242\0\0rV\0\1\316\253d\27\3\0\3\4\3C\0\0\1\0\0\0\254a\1\0\316\253d\27"..., 8192, 181288960) = 8192
712:38866 pread(257, "\6\242\0\0cY\0\1\321\253d\27\3\0\3\4\301c\0\0\1\0\1\0\254a\1\0\321\253d\27"..., 65536, 187457536) = 65536
719:38866 pread(257, "\6\242\0\0oY\0\1\321\253d\27\3\0\3\4\242Q\0\0\1\0\0\0\254a\1\0\321\253d\27"..., 65536, 187555840) = 65536
724:38866 pread(257, "\6\242\0\0\374Y\0\1\321\253d\27\3\0\3\4\3125\0\0\1\0\0\0\254a\1\0\321\253d\27"..., 8192, 188710912) = 8192
731:38866 pread(257, "\6\242\0\0\4\\\0\1\327\253d\27\3\0\3\4\4,\0\0\1\22@\0\254a\1\0\327\253d\27"..., 8192, 192970752) = 8192
738:38866 pread(257, "\6\242\0\0Ye\0\1\341\253d\27\3\0\3\4\33\374\0\0\1\0\0\0\254a\1\0\341\253d\27"..., 8192, 212541440) = 8192
743:38866 pread(257, "\6\242\0\0\1g\0\1\343\253d\27\3\0\3\4\217A\0\0\1\0\0\0\254a\1\0\343\253d\27"..., 8192, 216014848) = 8192
750:38866 pread(257, "\6\242\0\0<s\0\1\363\253d\27\3\0\3\4\31\5\0\0\1\0\0\0\254a\1\0\363\253d\27"..., 65536, 241664000) = 65536
757:38866 pread(257, "\6\242\0\0\325s\0\1\363\253d\27\3\0\3\0043\315\0\0\1\0\37\0\254a\1\0\363\253d\27"..., 8192, 242917376) = 8192
762:38866 pread(257, "\6\242\0\0\35t\0\1\367\253d\27\3\0\3\4\220m\0\0\1\0\36\0\254a\1\0\367\253d\27"..., 65536, 243507200) = 65536
769:38866 pread(257, "\6\242\0\0xt\0\1\370\253d\27\3\0\1\4\377E\0\0\1\0\0\0\254a\1\0\367\253d\27"..., 8192, 244252672) = 8192
774:38866 pread(257, "\6\242\0\0\27u\0\1\366\253d\27\3\0\3\4\207\317\0\0\1\0\0\0\254a\1\0\366\253d\27"..., 8192, 245555200) = 8192
781:38866 pread(257, "\6\242\0\0qw\0\1\370\253d\27\3\0\3\4S\344\0\0\1\0\0\0\254a\1\0\370\253d\27"..., 8192, 250486784) = 8192
788:38866 pread(257, "\6\242\0\0\16x\0\1\374\253d\27\3\0\3\4\24\0\0\0\1\0\22\0\254a\1\0\374\253d\27"..., 65536, 251772928) = 65536
793:38866 pread(257, "\6\242\0\0\226x\0\1\374\253d\27\3\0\3\4s\32\0\0\1\0\0\0\254a\1\0\374\253d\27"..., 8192, 252887040) = 8192
800:38866 pread(257, "\6\242\0\0009y\0\1\373\253d\27\3\0\3\4\35\273\0\0\1\0\0\0\254a\1\0\373\253d\27"..., 8192, 254222336) = 8192
805:38866 pread(257, "\6\242\0\0,z\0\1\376\253d\27\3\0\1\4a\361\0\0\1\0\20\0\254a\1\0\375\253d\27"..., 8192, 256212992) = 8192
812:38866 pread(257, "\6\242\0\0\207\210\0\1\20\254d\27\3\0\3\4\177{\0\0\1\0\0\0\254a\1\0\20\254d\27"..., 8192, 286318592) = 8192
819:38866 pread(257, "\6\242\0\0\242\212\0\1\22\254d\27\3\0\3\4\201l\0\0\1\0\0\0\254a\1\0\22\254d\27"..., 8192, 290734080) = 8192
824:38866 pread(257, "\6\242\0\0\362\213\0\1\21\254d\27\3\0\3\4\343\324\0\0\1\0\0\0\254a\1\0\21\254d\27"..., 8192, 293486592) = 8192
831:38866 pread(257, "\6\242\0\0\210\215\0\1\24\254d\27\3\0\3\4<i\0\0\1\0\0\0\254a\1\0\24\254d\27"..., 65536, 296812544) = 65536
838:38866 pread(257, "\6\242\0\0\375\215\0\1\24\254d\27\3\0\3\0045I\0\0\1\0\0\0\254a\1\0\24\254d\27"..., 8192, 297771008) = 8192
843:38866 pread(257, "\6\242\0\0\25\217\0\1\24\254d\27\3\0\3\4S\204\0\0\1\0\17\0\254a\1\0\24\254d\27"..., 8192, 300064768) = 8192
850:38866 pread(257, "\6\242\0\0q\224\0\1\37\254d\27\3\0\3\4\223-\0\0\1\0\0\0\254a\1\0\37\254d\27"..., 65536, 311304192) = 65536
--//这里读8块,也与前面复合.
859:38866 pread(257, "\6\242\0\0\341\224\0\1\37\254d\27\3\0\3\4\367\271\0\0\1\0\0\0\254a\1\0\37\254d\27"..., 8192, 312221696) = 8192
864:38866 pread(257, "\6\242\0\0\353\235\0\1)\254d\27\3\0\3\4kF\0\0\1\0\36\0\254a\1\0)\254d\27"..., 8192, 331177984) = 8192
871:38866 pread(257, "\6\242\0\0Z\241\0\1/\254d\27\3\0\1\4B\267\0\0\1\0\32\0\254a\1\0.\254d\27"..., 8192, 338378752) = 8192
--//注意行号,WAIT #140334076535760应该从这里结束.
925:38866 pread(257, "\6\242\0\0#\2\0\1j\250d\27\3\0\2\4a\244\0\0\1\0\0\0\254a\1\0h\250d\27"..., 40960, 4481024) = 40960
936:38866 pread(257, "\6\242\0\0(\2\0\1\207\250d\27\3\0\3\4\234\343\0\0\1\22@\0\254a\1\0\207\250d\27"..., 65536, 4521984) = 65536
959:38866 pread(257, "\6\242\0\0001\2\0\1\210\250d\27\3\0\3\4\20\233\0\0\1\0\0\0\254a\1\0\210\250d\27"..., 57344, 4595712) = 57344
980:38866 pread(257, "\6\242\0\0\240\2\0\1\211\250d\27\3\0\3\4y\16\0\0\1\0\0\0\254a\1\0\211\250d\27"..., 65536, 5505024) = 65536
1003:38866 pread(257, "\6\242\0\0\251\2\0\1\212\250d\27\3\0\3\4\207N\0\0\1\0\30\0\254a\1\0\212\250d\27"..., 57344, 5578752) = 57344


--//分析:
213:38866 pread(257, "#\242\0\0\"\2\0\1.\254d\27\3\0\2\4:\313\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 4472832) = 8192
216:38866 pread(257, " \242\0\0\0\3\0\1\234\250d\27\3\0\f\4\265L\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 6291456) = 8192
221:38866 pread(257, "!\242\0\0!\2\0\1/\254d\27\3\0\1\4j\323\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 8192, 4464640) = 8192

--//4472832/8192 = 546
--//6291456/8192 = 768
--//4464640/8192 = 545

WAIT #140334076535760: nam='db file sequential read' ela= 130 file#=4 block#=546 blocks=1 obj#=90540 tim=1521770828837576
WAIT #140334076535760: nam='db file sequential read' ela= 117 file#=4 block#=768 blocks=1 obj#=90540 tim=1521770828837966
WAIT #140334076535760: nam='db file sequential read' ela= 107 file#=4 block#=545 blocks=1 obj#=90540 tim=1521770828838464
WAIT #140334076535760: nam='db file parallel read' ela= 12239 files=1 blocks=127 requests=127 obj#=90540 tim=1521770828851403
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
WAIT #140334076535760: nam='db file sequential read' ela= 118 file#=4 block#=786 blocks=1 obj#=90540 tim=1521770828852240
WAIT #140334076535760: nam='db file sequential read' ela= 112 file#=3 block#=160 blocks=1 obj#=0 tim=1521770828852567
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
WAIT #140334076535760: nam='db file sequential read' ela= 114 file#=4 block#=1214 blocks=1 obj#=90540 tim=1521770828853324

357:38866 pread(257, "\6\242\0\0\22\3\0\1\232\250d\27\3\0\3\4\30\314\0\0\1\0\0\0\254a\1\0\232\250d\27"..., 8192, 6438912) = 8192
367:38866 pread(257, "\6\242\0\0\276\4\0\1\311\250d\27\3\0\1\4\234\302\0\0\1\0\2\0\254a\1\0\276\250d\27"..., 8192, 9945088) = 8192

--//跳过127个pread后
--//6438912/8192 = 786
--//9945088/8192 = 1214
--//注意@行,对象是file#=3.对于undo表空间. 注意:obj#=0

--//再看看最后4行:
WAIT #140334076535760: nam='db file scattered read' ela= 158 file#=4 block#=38001 blocks=8 obj#=90540 tim=1521770828902991
WAIT #140334076535760: nam='db file sequential read' ela= 110 file#=4 block#=38113 blocks=1 obj#=90540 tim=1521770828903877
WAIT #140334076535760: nam='db file sequential read' ela= 109 file#=4 block#=40427 blocks=1 obj#=90540 tim=1521770828904472
WAIT #140334076535760: nam='db file sequential read' ela= 110 file#=4 block#=41306 blocks=1 obj#=90540 tim=1521770828905165

850:38866 pread(257, "\6\242\0\0q\224\0\1\37\254d\27\3\0\3\4\223-\0\0\1\0\0\0\254a\1\0\37\254d\27"..., 65536, 311304192) = 65536
859:38866 pread(257, "\6\242\0\0\341\224\0\1\37\254d\27\3\0\3\4\367\271\0\0\1\0\0\0\254a\1\0\37\254d\27"..., 8192, 312221696) = 8192
864:38866 pread(257, "\6\242\0\0\353\235\0\1)\254d\27\3\0\3\4kF\0\0\1\0\36\0\254a\1\0)\254d\27"..., 8192, 331177984) = 8192
871:38866 pread(257, "\6\242\0\0Z\241\0\1/\254d\27\3\0\1\4B\267\0\0\1\0\32\0\254a\1\0.\254d\27"..., 8192, 338378752) = 8192

311304192/8192 = 38001
312221696/8192 = 38113
331177984/8192 = 40427
338378752/8192 = 41306
--//全部复合.

目录
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