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High Db file sequential reads

newbiegalAug 8 2013 — edited Aug 8 2013

Hi Friends,

Our client reports slowness in a program takes about 12-13 hours that same program runs in about an hour in our database with the same data. Here is the tkprof output they sent us.. It's a huge file so I'm copying the overall run times from the tkprof. It looks like the db file sequential reads take the most time.  Please give some suggestions on how to reduce this wait.. Since the same sql's/program run faster in our database with the same amount of data, I'm guessing it is not the application or the sql tuning.. Will increasing their db_block_buffers help? Please advice.

********************************************************************************

OVERALL TOTALS FOR ALL NON-RECURSIVE STATEMENTS

call     count       cpu    elapsed       disk      query    current        rows

------- ------  -------- ---------- ---------- ---------- ----------  ----------

Parse        5      0.05       0.06          0        886          8           0

Execute 1267249    166.07    5217.69      60158     336754    3171892      157586

Fetch   1116142   2969.76    8992.03      73748   16401909       9455     4305627

------- ------  -------- ---------- ---------- ---------- ----------  ----------

total   2383396   3135.89   14209.79     133906   16739549    3181355     4463213

Misses in library cache during parse: 5

Misses in library cache during execute: 30

Elapsed times include waiting on following events:

  Event waited on                             Times   Max. Wait  Total Waited

  ----------------------------------------   Waited  ----------  ------------

  SQL*Net break/reset to client               18694        0.03          8.71

  SQL*Net message to client                 3708663        0.00          3.01

  SQL*Net message from client               3708663      349.68       5021.96

  db file sequential read                    133910        8.76       7561.10

  control file sequential read                 2187        0.00          0.02

  Data file init write                          178        0.08          0.11

  direct path sync                               81        1.57         23.54

  flashback buf free by RVWR                     89        0.97         12.53

  control file parallel write                   567        2.22         26.77

  db file single write                           81        2.60          5.80

  log file sync                                 323        0.09         14.61

  SQL*Net more data to client                586129        0.02          7.46

  rdbms ipc reply                               604        1.96       1111.22

  db file scattered read                         23        0.43          1.66

  undo segment extension                      13803        0.10       1358.43

OVERALL TOTALS FOR ALL RECURSIVE STATEMENTS

call     count       cpu    elapsed       disk      query    current        rows

------- ------  -------- ---------- ---------- ---------- ----------  ----------

Parse    18345      0.57       0.61          0          0        259           0

Execute 306998     25.04    2715.93      44678      39813     227194       33891

Fetch   294444      7.08       9.09         12     619345          0      264205

------- ------  -------- ---------- ---------- ---------- ----------  ----------

total   619787     32.69    2725.64      44690     659158     227453      298096

Misses in library cache during parse: 132

Misses in library cache during execute: 135

Elapsed times include waiting on following events:

  Event waited on                             Times   Max. Wait  Total Waited

  ----------------------------------------   Waited  ----------  ------------

  SQL*Net message to client                       2        0.00          0.00

  SQL*Net message from client                     2        0.03          0.03

  db file sequential read                     44755        9.05       2435.33

  control file sequential read                  918        0.00          0.00

  Data file init write                           71        0.00          0.00

  direct path sync                               34        2.14         12.77

  flashback buf free by RVWR                     40        0.97          7.19

  control file parallel write                   238        0.63         10.78

  db file single write                           34        0.42          2.03

  rdbms ipc reply                               115        1.95        198.80

   45  user  SQL statements in session.

27182  internal SQL statements in session.

27227  SQL statements in session.

********************************************************************************

Trace file: trace1.trc

Trace file compatibility: 10.01.00

Sort options: default

       1  session in tracefile.

      45  user  SQL statements in trace file.

   27182  internal SQL statements in trace file.

   27227  SQL statements in trace file.

      80  unique SQL statements in trace file.

12020231  lines in trace file.

   21774  elapsed seconds in trace file.

THanks a lot

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Locked on Sep 5 2013
Added on Aug 8 2013
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