Logical reads per second

I have two databases - one is a clone of the other, amde a few months ago. Database A has somewhat more data, since it's the active production database, but not significantly more - perhaps 10% greater. They are on different boxes. Database A is on a Sun 280R 2-processor box. Database B is on a Dell 2950 with 2 dual-core processors. So this isn't exactly comparing apples to apples. However, when I run the same query on the two databases, I get radically different results. Against Database A, the query takes about 7 minutes. On Database B, it takes about 2 seconds. Logical reads per second on Database A reach 80,000-90,000; on Database B, they're about 3,000. There are a few configuration differences (both databases use automatic memory management):
Database A Database B
db_file_multiblock_read_count 64 16
log_buffer 14290432 2104832
open_cursors 1250 300
sga_max_size 4194304000 536870912
sga_target 2634022912 536870912
shared_pool_reserved_size 38587596 7340032
The timings were taken off-hours so neither database would be busy. I'm baffled by the extreme difference in execution times. Any help appreciated!
Thanks,
Harry
Edited by: harryb on Apr 8, 2009 7:26 PM

OK, let's start here....
Database A (TEMPOP)
SQL> show parameter optimizer
NAME TYPE VALUE
optimizer_dynamic_sampling integer 2
optimizer_features_enable string 10.2.0.3
optimizer_index_caching integer 0
optimizer_index_cost_adj integer 100
optimizer_mode string ALL_ROWS
optimizer_secure_view_merging boolean TRUE
SQL> show parameter db_file_multi
NAME TYPE VALUE
db_file_multiblock_read_count integer 64
SQL> show parameter db_block_size
NAME TYPE VALUE
db_block_size integer 8192
===================================================
Database B (TEMPO11)
SQL> show parameter optimizer
NAME TYPE VALUE
optimizer_dynamic_sampling integer 2
optimizer_features_enable string 10.2.0.1
optimizer_index_caching integer 0
optimizer_index_cost_adj integer 100
optimizer_mode string ALL_ROWS
optimizer_secure_view_merging boolean TRUE
SQL> show parameter db_file_multi
NAME TYPE VALUE
db_file_multiblock_read_count integer 16
SQL> show parameter db_block_size
NAME TYPE VALUE
db_block_size integer 8192
=================================================================
Now for the query that's causing the problem:
SELECT dsk_document_attribute.value_text inspect_permit_no,
          NVL (activity_task_list.revised_due_date,
               activity_task_list.default_due_date
             inspect_report_due_date,
          agency_interest.master_ai_id agency_interest_id,
          agency_interest.master_ai_name agency_interest_name,
          get_county_code_single (agency_interest.master_ai_id)
             parish_or_county_code,
          agency_interest_address.physical_address_line_1 inspect_addr_1,
          agency_interest_address.physical_address_line_2 inspect_addr_2,
          agency_interest_address.physical_address_line_3 inspect_addr_3,
          agency_interest_address.physical_address_municipality inspect_city,
          agency_interest_address.physical_address_state_code state_id,
          agency_interest_address.physical_address_zip inspect_zip,
          person.master_person_first_name person_first_name,
          person.master_person_middle_initial person_middle_initial,
          person.master_person_last_name person__last_name,
          SUBSTR (person_telecom.address_or_phone, 1, 14) person_phone,
          activity_task_list.requirement_id
   FROM dsk_document_attribute,
        agency_interest,
        activity_task_list,
        agency_interest_address,
        dsk_central_file dsk_aaa,
        dsk_central_file dsk_frm,
        person,
        person_telecom
   WHERE agency_interest.int_doc_id = 0
         AND agency_interest.master_ai_id =
               agency_interest_address.master_ai_id
         AND agency_interest.int_doc_id = agency_interest_address.int_doc_id
         AND agency_interest.master_ai_id = dsk_frm.master_ai_id
         AND dsk_aaa.int_doc_id = activity_task_list.int_doc_id
         AND dsk_frm.int_doc_id = dsk_document_attribute.int_doc_id
         AND dsk_frm.doc_type_specific_code =
               dsk_document_attribute.doc_type_specific_code
         AND dsk_frm.activity_category_code = 'PER'
         AND dsk_frm.activity_class_code = 'GNP'
         AND dsk_frm.activity_type_code IN ('MAB', 'NAB', 'REB')
         AND dsk_frm.program_code = '80'
         AND dsk_frm.doc_type_general_code = 'FRM'
         AND dsk_frm.doc_type_specific_code = 'PERSET'
         AND dsk_aaa.doc_template_id = 2000
         AND dsk_frm.master_ai_id = dsk_aaa.master_ai_id
         AND dsk_frm.activity_category_code = dsk_aaa.activity_category_code
         AND dsk_frm.program_code = dsk_aaa.program_code
         AND dsk_frm.activity_class_code = dsk_aaa.activity_class_code
         AND dsk_frm.activity_type_code = dsk_aaa.activity_type_code
         AND dsk_frm.activity_year = dsk_aaa.activity_year
         AND dsk_frm.activity_num = dsk_aaa.activity_num
         AND dsk_document_attribute.doc_attribute_code = 'PERMIT_NO'
         AND activity_task_list.requirement_id IN ('3406', '3548', '3474')
         AND activity_task_list.reference_task_id = 0
         AND NVL (activity_task_list.status_code, '$$$') <> '% '
         AND person.master_person_id(+) =
               f_get_gp_contact (agency_interest.master_ai_id)
         AND person.int_doc_id(+) = 0
         AND person.master_person_id = person_telecom.master_person_id(+)
         AND person.int_doc_id = person_telecom.int_doc_id(+)
         AND person_telecom.telecom_type_code(+) = 'wp';Here's the explain plan for Database A, where the query takes 7-8 minutes or more:
PLAN_TABLE_OUTPUT
| Id | Operation                           | Name                       | Rows | Bytes | Cost (%CPU)|
|   0 | SELECT STATEMENT                    |                            |     1 |   253 |    34   (3)|
|   1 | NESTED LOOPS                       |                            |     1 |   253 |    34   (3)|
|   2 |   NESTED LOOPS                      |                            |     1 |   224 |    32   (0)|
|   3 |    NESTED LOOPS OUTER               |                            |     1 |   169 |    31   (0)|
|   4 |     NESTED LOOPS OUTER              |                            |     1 |   144 |    29   (0)|
|   5 |      NESTED LOOPS                   |                            |     1 |   122 |    27   (0)|
|   6 |       NESTED LOOPS                  |                            |     1 |    81 |    26   (0)|
PLAN_TABLE_OUTPUT
|   7 |        NESTED LOOPS                 |                            |     1 |    48 |    19   (0)|
|   8 |         INLIST ITERATOR             |                            |       |       |            |
|* 9 |          TABLE ACCESS BY INDEX ROWID| ACTIVITY_TASK_LIST         |     1 |    21 |    17   (0)|
|* 10 |           INDEX RANGE SCAN          | ACTIVITY_TASK_LIST_FK11    |   106 |       |     4   (0)|
|* 11 |         TABLE ACCESS BY INDEX ROWID | DSK_CENTRAL_FILE           |     1 |    27 |     2   (0)|
|* 12 |          INDEX UNIQUE SCAN          | PK_DSK_CENTRAL_FILE        |     1 |       |     1   (0)|
|* 13 |        TABLE ACCESS BY INDEX ROWID | DSK_CENTRAL_FILE           |     1 |    33 |     7   (0)|
|* 14 |         INDEX RANGE SCAN            | CF_MASTER_AI_ID_IND        |     9 |       |     2   (0)|
| 15 |       TABLE ACCESS BY INDEX ROWID   | AGENCY_INTEREST            |     1 |    41 |     1   (0)|
|* 16 |        INDEX UNIQUE SCAN            | PK_AGENCY_INTEREST         |     1 |       |     0   (0)|
| 17 |      TABLE ACCESS BY INDEX ROWID    | PERSON                     |     1 |    22 |     2   (0)|
PLAN_TABLE_OUTPUT
|* 18 |       INDEX UNIQUE SCAN             | PK_PERSON                  |     1 |       |     1   (0)|
| 19 |     TABLE ACCESS BY INDEX ROWID     | PERSON_TELECOM             |     1 |    25 |     2   (0)|
|* 20 |      INDEX UNIQUE SCAN              | PK_PERSON_TELECOM          |     1 |       |     1   (0)|
| 21 |    TABLE ACCESS BY INDEX ROWID      | AGENCY_INTEREST_ADDRESS    |     1 |    55 |     1   (0)|
|* 22 |     INDEX UNIQUE SCAN               | PK_AGENCY_INTEREST_ADDRESS |     1 |       |     0   (0)|
| 23 |   TABLE ACCESS BY INDEX ROWID       | DSK_DOCUMENT_ATTRIBUTE     |     1 |    29 |     1   (0)|
|* 24 |    INDEX UNIQUE SCAN                | PK_DSK_DOCUMENT_ATTRIBUTE |     1 |       |     0   (0)|
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   9 - filter("ACTIVITY_TASK_LIST"."REFERENCE_TASK_ID"=0 AND
              NVL("ACTIVITY_TASK_LIST"."STATUS_CODE",'$$$')<>'% ')
10 - access("ACTIVITY_TASK_LIST"."REQUIREMENT_ID"=3406 OR
              "ACTIVITY_TASK_LIST"."REQUIREMENT_ID"=3474 OR "ACTIVITY_TASK_LIST"."REQUIREMENT_ID"=3548)
11 - filter("DSK_AAA"."DOC_TEMPLATE_ID"=2000 AND "DSK_AAA"."ACTIVITY_CLASS_CODE"='GNP' AND
              "DSK_AAA"."PROGRAM_CODE"='80' AND "DSK_AAA"."ACTIVITY_CATEGORY_CODE"='PER' AND
              ("DSK_AAA"."ACTIVITY_TYPE_CODE"='MAB' OR "DSK_AAA"."ACTIVITY_TYPE_CODE"='NAB' OR
              "DSK_AAA"."ACTIVITY_TYPE_CODE"='REB'))
12 - access("ACTIVITY_TASK_LIST"."INT_DOC_ID"="DSK_AAA"."INT_DOC_ID")
13 - filter("DSK_FRM"."ACTIVITY_CLASS_CODE"='GNP' AND "DSK_FRM"."PROGRAM_CODE"='80' AND
PLAN_TABLE_OUTPUT
              "DSK_FRM"."DOC_TYPE_SPECIFIC_CODE"='PERSET' AND "DSK_FRM"."ACTIVITY_CATEGORY_CODE"='PER' AND
              "DSK_FRM"."DOC_TYPE_GENERAL_CODE"='FRM' AND ("DSK_FRM"."ACTIVITY_TYPE_CODE"='MAB' OR
              "DSK_FRM"."ACTIVITY_TYPE_CODE"='NAB' OR "DSK_FRM"."ACTIVITY_TYPE_CODE"='REB') AND
              "DSK_FRM"."ACTIVITY_TYPE_CODE"="DSK_AAA"."ACTIVITY_TYPE_CODE" AND
              "DSK_FRM"."ACTIVITY_YEAR"="DSK_AAA"."ACTIVITY_YEAR" AND
              "DSK_FRM"."ACTIVITY_NUM"="DSK_AAA"."ACTIVITY_NUM")
14 - access("DSK_FRM"."MASTER_AI_ID"="DSK_AAA"."MASTER_AI_ID")
16 - access("AGENCY_INTEREST"."MASTER_AI_ID"="DSK_FRM"."MASTER_AI_ID" AND
              "AGENCY_INTEREST"."INT_DOC_ID"=0)
18 - access("PERSON"."MASTER_PERSON_ID"(+)="F_GET_GP_CONTACT"("AGENCY_INTEREST"."MASTER_AI_ID
              ") AND "PERSON"."INT_DOC_ID"(+)=0)
PLAN_TABLE_OUTPUT
20 - access("PERSON"."MASTER_PERSON_ID"="PERSON_TELECOM"."MASTER_PERSON_ID"(+) AND
              "PERSON_TELECOM"."TELECOM_TYPE_CODE"(+)='wp' AND
              "PERSON"."INT_DOC_ID"="PERSON_TELECOM"."INT_DOC_ID"(+))
22 - access("AGENCY_INTEREST"."MASTER_AI_ID"="AGENCY_INTEREST_ADDRESS"."MASTER_AI_ID" AND
              "AGENCY_INTEREST_ADDRESS"."INT_DOC_ID"=0)
24 - access("DSK_FRM"."INT_DOC_ID"="DSK_DOCUMENT_ATTRIBUTE"."INT_DOC_ID" AND
              "DSK_DOCUMENT_ATTRIBUTE"."DOC_ATTRIBUTE_CODE"='PERMIT_NO' AND
              "DSK_DOCUMENT_ATTRIBUTE"."DOC_TYPE_SPECIFIC_CODE"='PERSET')============================================================================
Here's the explan plan output for Database B, where the query takes 2-3 seconds:
PLAN_TABLE_OUTPUT
| Id | Operation                           | Name                       | Rows | Bytes | Cost (%CPU)|
|   0 | SELECT STATEMENT                    |                            |     1 |   289 |    39   (0)|
|   1 | NESTED LOOPS OUTER                 |                            |     1 |   289 |    39   (0)|
|   2 |   NESTED LOOPS                      |                            |     1 |   260 |    37   (0)|
|   3 |    NESTED LOOPS                     |                            |     1 |   205 |    36   (0)|
|   4 |     NESTED LOOPS OUTER              |                            |     1 |   172 |    35   (0)|
|   5 |      NESTED LOOPS                   |                            |     1 |   145 |    34   (0)|
|   6 |       NESTED LOOPS                  |                            |     1 |   104 |    33   (0)|
PLAN_TABLE_OUTPUT
|   7 |        NESTED LOOPS                 |                            |     1 |    61 |    26   (0)|
|   8 |         INLIST ITERATOR             |                            |       |       |            |
|* 9 |          TABLE ACCESS BY INDEX ROWID| ACTIVITY_TASK_LIST         |     1 |    25 |    24   (0)|
|* 10 |           INDEX RANGE SCAN          | ACTIVITY_TASK_LIST_FK11    |   145 |       |     4   (0)|
|* 11 |         TABLE ACCESS BY INDEX ROWID | DSK_CENTRAL_FILE           |     1 |    36 |     2   (0)|
|* 12 |          INDEX UNIQUE SCAN          | PK_DSK_CENTRAL_FILE        |     1 |       |     1   (0)|
|* 13 |        TABLE ACCESS BY INDEX ROWID | DSK_CENTRAL_FILE           |     1 |    43 |     7   (0)|
|* 14 |         INDEX RANGE SCAN            | CF_MASTER_AI_ID_IND        |     9 |       |     2   (0)|
| 15 |       TABLE ACCESS BY INDEX ROWID   | AGENCY_INTEREST            |     1 |    41 |     1   (0)|
|* 16 |        INDEX UNIQUE SCAN            | PK_AGENCY_INTEREST         |     1 |       |     0   (0)|
| 17 |      TABLE ACCESS BY INDEX ROWID    | PERSON                     |     8 |   216 |     1   (0)|
PLAN_TABLE_OUTPUT
|* 18 |       INDEX UNIQUE SCAN             | PK_PERSON                  |     1 |       |     0   (0)|
| 19 |     TABLE ACCESS BY INDEX ROWID     | DSK_DOCUMENT_ATTRIBUTE     |     1 |    33 |     1   (0)|
|* 20 |      INDEX UNIQUE SCAN              | PK_DSK_DOCUMENT_ATTRIBUTE |     1 |       |     0   (0)|
| 21 |    TABLE ACCESS BY INDEX ROWID      | AGENCY_INTEREST_ADDRESS    |     1 |    55 |     1   (0)|
|* 22 |     INDEX UNIQUE SCAN               | PK_AGENCY_INTEREST_ADDRESS |     1 |       |     0   (0)|
| 23 |   TABLE ACCESS BY INDEX ROWID       | PERSON_TELECOM             |     1 |    29 |     2   (0)|
|* 24 |    INDEX UNIQUE SCAN                | PK_PERSON_TELECOM          |     1 |       |     1   (0)|
Predicate Information (identified by operation id):
PLAN_TABLE_OUTPUT
   9 - filter("ACTIVITY_TASK_LIST"."REFERENCE_TASK_ID"=0 AND
              NVL("ACTIVITY_TASK_LIST"."STATUS_CODE",'$$$')<>'% ')
10 - access("ACTIVITY_TASK_LIST"."REQUIREMENT_ID"=3406 OR
              "ACTIVITY_TASK_LIST"."REQUIREMENT_ID"=3474 OR "ACTIVITY_TASK_LIST"."REQUIREMENT_ID"=3548)
11 - filter("DSK_AAA"."DOC_TEMPLATE_ID"=2000 AND "DSK_AAA"."ACTIVITY_CLASS_CODE"='GNP' AND
              "DSK_AAA"."PROGRAM_CODE"='80' AND "DSK_AAA"."ACTIVITY_CATEGORY_CODE"='PER' AND
              ("DSK_AAA"."ACTIVITY_TYPE_CODE"='MAB' OR "DSK_AAA"."ACTIVITY_TYPE_CODE"='NAB' OR
              "DSK_AAA"."ACTIVITY_TYPE_CODE"='REB'))
12 - access("ACTIVITY_TASK_LIST"."INT_DOC_ID"="DSK_AAA"."INT_DOC_ID")
13 - filter("DSK_FRM"."DOC_TYPE_SPECIFIC_CODE"='PERSET' AND
PLAN_TABLE_OUTPUT
              "DSK_FRM"."ACTIVITY_CLASS_CODE"='GNP' AND "DSK_FRM"."PROGRAM_CODE"='80' AND
              "DSK_FRM"."DOC_TYPE_GENERAL_CODE"='FRM' AND "DSK_FRM"."ACTIVITY_CATEGORY_CODE"='PER' AND
              ("DSK_FRM"."ACTIVITY_TYPE_CODE"='MAB' OR "DSK_FRM"."ACTIVITY_TYPE_CODE"='NAB' OR
              "DSK_FRM"."ACTIVITY_TYPE_CODE"='REB') AND "DSK_FRM"."ACTIVITY_TYPE_CODE"="DSK_AAA"."ACTIVITY_TY
              PE_CODE" AND "DSK_FRM"."ACTIVITY_YEAR"="DSK_AAA"."ACTIVITY_YEAR" AND
              "DSK_FRM"."ACTIVITY_NUM"="DSK_AAA"."ACTIVITY_NUM")
14 - access("DSK_FRM"."MASTER_AI_ID"="DSK_AAA"."MASTER_AI_ID")
16 - access("AGENCY_INTEREST"."MASTER_AI_ID"="DSK_FRM"."MASTER_AI_ID" AND
              "AGENCY_INTEREST"."INT_DOC_ID"=0)
18 - access("PERSON"."MASTER_PERSON_ID"(+)="F_GET_GP_CONTACT"("AGENCY_INTEREST"."MASTER_AI_ID
              ") AND "PERSON"."INT_DOC_ID"(+)=0)
PLAN_TABLE_OUTPUT
20 - access("DSK_FRM"."INT_DOC_ID"="DSK_DOCUMENT_ATTRIBUTE"."INT_DOC_ID" AND
              "DSK_DOCUMENT_ATTRIBUTE"."DOC_ATTRIBUTE_CODE"='PERMIT_NO' AND
              "DSK_DOCUMENT_ATTRIBUTE"."DOC_TYPE_SPECIFIC_CODE"='PERSET')
22 - access("AGENCY_INTEREST"."MASTER_AI_ID"="AGENCY_INTEREST_ADDRESS"."MASTER_AI_ID" AND
              "AGENCY_INTEREST_ADDRESS"."INT_DOC_ID"=0)
24 - access("PERSON"."MASTER_PERSON_ID"="PERSON_TELECOM"."MASTER_PERSON_ID"(+) AND
              "PERSON_TELECOM"."TELECOM_TYPE_CODE"(+)='wp' AND
              "PERSON"."INT_DOC_ID"="PERSON_TELECOM"."INT_DOC_ID"(+))===============================================================================
Edited by: harryb on Apr 9, 2009 3:29 PM

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Russ_XP:
I think you are correct about fast writes. I googled the heck out of that last night and couldn't find any reference to enabling or disabling fast writes on PCI-E.
The drive is SATA-1. The Neo4-F is not SATA-2 enabled (there is a hack for it though). From memory I think it's a Western Digital WD1600-something, 7200 RPM dirve. I've tried it on both SATA buses and tried disabling the unused bus in BIOS.
I'm pretty sure I can dig up an old PATA drive somewhere and give that a try.
Gpalmer:
True enough, and I don't have these problems under Fedora. Sadly this is a cross-platform game development box, I need both XP and Fedora working.
Black_God:
Nope, this is a clean install. Although I wonder, could any of the built in XP update and security tools be causing this? I have disabled Windows firewall and virus protection monitoring.

10,000 Recorc Per Second (In EJB 3.0)

hi all,
i have some mission critical tasks into my project, is it possible to persist 10 000 record per seconds,
1. AS - JBoss Application Server 4.0.4GA
2. Database - Oracle 10G 10.2.0.1
3.EJB - 3.0 Framework
4.OS - SunOS 5.10
4.Server - Memory: 16G phys mem, 31G swap, 16 CPU,
i know that i need performace
here is my configurations about performance
1. JVM Config Into JBoss
JAVA_OPTS="-server -Xmx3168m -Xms2144m -Xmn1g -Xss256k -d64 -XX:PermSize=128m -XX:MaxPermSize=256m
   -Dsun.rmi.dgc.client.gcInterval=3600000 -Dsun.rmi.dgc.server.gcInterval=3600000
    -XX:ParallelGCThreads=20 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC
    -XX:SurvivorRatio=8 -XX:TargetSurvivorRatio=90 -XX:MaxTenuringThreshold=31 -XX:+AggressiveOpts
    -verbose:gc -XX:+PrintGCTimeStamps -XX:+PrintGCDetails -XX:+PrintTenuringDistribution2. also i configure my database.xml file
<?xml version="1.0" encoding="UTF-8"?>
<datasources>
<xa-datasource>
    <jndi-name>XAOracleDS</jndi-name>
    <track-connection-by-tx/>
    <isSameRM-override-value>false</isSameRM-override-value>
    <xa-datasource-class>oracle.jdbc.xa.client.OracleXADataSource</xa-datasource-class>
    <xa-datasource-property name="URL">jdbc:oracle:thin:@192.168.9.136:1521:STR</xa-datasource-property>
    <xa-datasource-property name="User">SRVPROV</xa-datasource-property>
    <xa-datasource-property name="Password">SRVPROV</xa-datasource-property>
    <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleExceptionSorter</exception-sorter-class-name>
    <min-pool-size>50</min-pool-size>
    <max-pool-size>200</max-pool-size>
    <metadata>
         <type-mapping>Oracle9i</type-mapping>
      </metadata>
</xa-datasource>
<mbean code="org.jboss.resource.adapter.jdbc.vendor.OracleXAExceptionFormatter"
         name="jboss.jca:service=OracleXAExceptionFormatter">
    <depends optional-attribute-name="TransactionManagerService">jboss:service=TransactionManager</depends>
</mbean>
</datasources>3. Also i have one simple Stlateless Session Bean
@Stateless
@Remote(UsageFasade.class)
public class UsageFasadeBean implements UsageFasade {
     @PersistenceContext(unitName = "CustomerCareOracle")
     private EntityManager oracleManager;
     @TransactionAttribute(TransactionAttributeType.REQUIRED)
     public long createUsage(UsageObject usageObject, UserContext context)
               throws UserManagerException, CCareException {
          try {
               oracleManager
                         .createNativeQuery("INSERT INTO USAGE "
                                   + " (ID, SESSION_ID, SUBSCRIBER_ID, RECDATE, STARTDATE, APPLIEDVERSION_ID, CHARGINGPROFILE_ID, TOTALTIME, TOTALUNITS, IDENTIFIERTYPE_ID, IDENTIFIER, PARTNO, CALLTYPE_ID, USAGETYPE, APARTY, BPARTY, CPARTY, IMEI, SPECIFICCALLTYPE, APN, SOURCELOCATION, SMSCADDRESS, MSC_ID, ENDREASON, USAGEORIGIN, BILL_ID, CONTRACT_ID) "
                                   + " VALUES(SEQ_USAGE_ID.NEXTVAL, NULL, NULL, SYSDATE, SYSDATE, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL) ");
               return 1;
          } catch (Exception e) {
}3. and into client side i have 200 Threads, each of them tried to call this method 50 times
my result is that i can persist 10000 record in 20 seconds, without hibernate, with hibernate i got worst result :(,
also i hear that it is good idea to use JDBC 3.0 driver for performance,
i download newest oracle jdbc jar file from oracle site
http://www.oracle.com/technology/software/tech/java/sqlj_jdbc/htdocs/jdbc_10201.html
is this jar file JDBC 3.0 driver ?
is there any hibernate performance configuration?
is it any more performance tuning into JBoss or EJB with entity beans?
can anybody help me ? or is there any doc which can help me ?
Regards,
Paata,
Message was edited by:
paata
Message was edited by:
paata

What makes you think that your database, just the database (with the box that it is on) can handle that rate?
What makes you think that your network can handle that?
While this is going on is this the ONLY traffic that will be on the network?

Newbie trying to understand the frame/fields per second concept on video

Do video camera shutter speeds (1/60sec) reflect an interlaced field or a full frame comprised of two interlaced fields per part of a second.
I suspect that a shutter setting of 1/60sec means it's not a full frame of video but is just an odd or even lined interlace field. Meaning that if I want to shoot 30fps I need to keep my shutter setting on 1/60sec.
But if that's really the case, then what am I exactly shooting per second if actual NTSC frame rate is 29.97fps? I mean, the first 2p frames can easily be divided into two fields each, but what about the remaining .97frame. How can you divide that into two fields of interlaced video lines?
Forgive my ignorance but books have a bad habit of not answering back when you don't understand something they say.
iMac Intel Duo-Core; Intel Mac mini single-core Mac OS X (10.4.6)
iMac Intel Duo-Core; Intel Mac mini single-core Mac OS X (10.4.6)

The shutter speed is not relevant. I can be either field based or progressive. The frame rate is not dependent on the shutter speed.

Calculating Frames Per Second Accurately

I tried searching the forums for suggestions or code used to calculate FPS accurately... But was ultimately unsuccessful.
I think I have a pretty basic understanding of how it works... but I'm still left wondering if there's a better... or correct way of attacking the problem.
What I started out doing is taken a pre-cycle time sample using System's currentTimeMillis method, followed by the main parts I'm executing in my program and then took a second time sample. I subtracted the post-cycle from the pre-cycle to get the time... and it occurred to me that the currentTimeMillis is not exactly reliable. As it says in the API, "For example, many operating systems measure time in units of tens of milliseconds," when discussing that method.
I then noticed the nanoTime method and decided to use that.
It quite honestly seems to work perfectly for what I'm trying to accomplish.
I pretty much used the same steps as before.
But now my problem is that I want to limit the amount of frames per second to 60.
I decided that I should try using the Thread class's sleep(long millis, int nanos) method.
It seemed like it would work... but to my dismay, it did not.
The milliseconds, for the most part, were correctly timed... but still not always. The nanoseconds even less so... but I knew that the nanoseconds would be less reliable-I decided to use microseconds. Using microseconds doesn't even work that well.
So I wondered if there was an even better way... maybe a more 'manual' approach to fixing my problem.
I would greatly appreciate any input/knowledge on the matter.

its quite simple. Windows has an API call that can set the timer precision (its all based on some interrupt interval - I forgot the precise details). This precision is system wide, so if one application does it it is immediately active for all other applications running at that time. Applications can only lower it, so if you set it to 1ms then some other application cannot force it to 5ms for example.
Now here comes JVM bug number two.
As said the interval differs per system - sometimes it is 10ms, sometimes it is 15ms. The JVM wrongfully assumes it is always 10ms however. Do a test: try to sleep for some time that is a multiple of 10 (without the long running thread hack active); you'll find that the precision still sucks. That is because in this specific case the JVM does NOT change the system wide timing precision. But if you sleep for any number of milliseconds that is not a multiple of 10 it will actually temporarily set the precision to 1ms.
So the rule is: as long as one thread goes to sleep the precision is set to 1ms. When the last sleeping thread wakes up, it is reset to what it was. Then it also doesn't matter for what amount of time you make your real thread sleep as the long sleeping thread will not be sleeping for an amount that is a multiple of 10, thus forcing the precision to 1ms.
Now say that you don't do the long sleeping thread hack and you make your own thread sleep for say 9ms, switching to 1ms precision temporarily. This behavior makes it so that sampling the passed time (before and after sleeping) can be imprecise; you'll find that most of the time you'll get sampling that matches the number of milliseconds you slept and sometimes it jumps to 10/15ms depending on the granularity of your system. This is a concurrency problem; sometimes the precision is reset before you get a chance to sample the current time.
So to recap to give 100% accuracy with System.currentTimeInMillis(), you need to keep a thread sleeping at all time so the precision stays at 1ms.
And then finally we come to bug #3, which is a problem in Windows itself: rapidly changing the precision (which happens when you make a single thread sleep for short intervals) can screw with the system clock. I don't know if this problem still exists in later iterations of Windows, but it is again a reason to do the long sleeping thread hack. Because this is a known issue I still call this a bug in the JVM because of the way they implemented the precision timer activation, which can trigger the problem in Windows. The command line switch mentioned in the above bug report SHOULD have fixed that... but you know, facepalm bug #4.
But at the end of the day: even if at least 4 bugs can be named regarding precise timing in Java under Windows, the root of all evil is still the way timing is implemented in Windows itself making life too difficult for the poor JVM devs. What were the MS devs thinking at the time?

Final Cut Pro X Image Sequence Export missing frames per second option?

I am using the trial version of Final Cut Pro X. I can export an image sequence but it will only allow me to do so at 30 frames per second -every single frame!
So a 10 min movie takes half an hour to export 20,000+ frames that no one on earth has time to look thru.
In my old Final Cut Express I was able to choose 1 or 2 frames per second, which was just right.
What am I missing?
Do I need to buy Quicktime Pro or Compressor to allow me to export image sequences without exporting every frame?
Why would Apple even have an image sequence export if it only allows you to export every frame, or it that only in the trial version?
Thank you

I found a free option for you, if you don't already have Compressor 4.
In FCPX create your movie. Then SHARE as a Master File.
Get MPEG Streamclip, which is a free app available here.
http://www.squared5.com/svideo/mpeg-streamclip-mac.html
Drag your Master File into MPEG Streamclip.
In MPEG Streamclip, select FILE/EXPORT TO OTHER FORMATS.
In FORMAT: choose IMAGE SEQUENCE
In OPTIONS, choose your frame rate.

1,000,000 updates per second?

How could you configure a coherence cluster to handle processing a million stock quotes per sec? The datafeed could be configured as a single app spewing out all 1,000,000/sec or it could be many apps producing proportionately fewer ticks/sec but in any case it's going to total a million/sec. Fractions of the feed spread among multiple physical servers sounds smartest. The quote Map.Entry would probably have a Key of String (or char[] if that's more efficient - i know the max length). The Value would be a price and a size so maybe just those two elements byte[]{Float,Integer} or a java object with Float and Integer member variables. I'd want to trigger actions based on market conditions when the planets align just right so I'm not simply ignoring these values or pub/sub'ing them out to client apps, I'm evaluating many of them simultaneously and using them as event triggers. Is something like that remotely possible? On how much hardware?
Thanks,
Andrew

Andrew,
Using partitioning, Coherence can handle 1 million updates per second, but the big question is how many updates per second do you need on the hottest instrument at the hottest time?
The other question is related to "the planets lining up", because that may imply a global view of the market, which becomes more difficult in a partitioned system.
To provide a high rate of change to data in a partitioned system, the data providers (those with a large amount of data or a high rate of change) should be in the cluster (not coming in over *Extend) to eliminate one hop. To avoid blocking on the tick update from the data provider, it should locally enqueue the update. The queue servicer (a separate thread) should either coalesce whatever ticks are in the queue into a single putAll(), or if every tick needs to be recorded (i.e. all three ticks in the queue like "change to 3.5", "change to 3.55", "change to 3.6" have to be published, instead of just the latest "change to 3.6") then it would batch up everything in the queue until it hits an item that it already has in its batch, and then do a putAll().
The use of that async publishing mode is what allows for the much higher throughput, particularly when a data provider is producing a huge number of ticks in a given period of time. You can make it even smoother (e.g. avoid outliers caused by some servers being slower) by having more local queues+services (partitioned by Coherence partition, or at the extreme by instrument). You can determine the Coherence partition using the KeyPartitioningStrategy returned from the PartitionedService for the ticks cache.
Peace,
Cameron Purdy | Oracle Coherence
http://coherence.oracle.com/

What is the most Frames Per Second NI-CAN can do?

My goal is to send 1000 Frames per Second on my CAN bus using the NI-CAN PCI 2 slot card I have. However the closest I have been able to do is 666 frames per second. This is sending 8 frames every 12 MS using an edited readmult example. Is there a way to do this with writemult? Or is there a hardware limit that I am trying to go past?
What can I mess with to get more frames? Increase Baudrate? Decrease the size of the frames? (I've tried both of those)
Other questions that should probably go in other posts (Frame API):
Is there a way to send/read the frames at the bit-level? I have found ways to manipulate Arbitration ID, Remote Frame, Data Length, and Data, but there are several other bits in a frame.
Is there a way to send a bad frame, one that would raise/cause an error frame?

Yes, I did break 1,000 Frames Per Second. I got up to 1,714 and 1,742 using two different methods. This is at 250 kbps, if you used 500 or 1 Mbps, you could get more frames. If you have 125 kbps, you might not be able to break 1,000 Frames per Second.
ncWriteMult is the key. You can load 512 frames in a queue at a time. I would put 256 on at a time and check to see if there was less than 256 frames left in the queue and if there was, load it up, that way the queue would never be empty. I went about it 2 ways, one was using ncGetAttribute to determine space left, and that got the faster method, however, I was also trying to read the messages to verify that it worked, and I had problems with logging every frame. It would also send the first 40 ncWriteMults quickly, as if the queue it was filling was much larger than 512.
The other way, was using trial and error to determine how many MS to sleep before writing the next batch of 256 frames. There are variables outside of my control that determined the time it would take and it would vary a few ms. I wanted a stable environment that could send forever without filling the queue so I went with a value that would wait 2 or 3 ms, depending on conditions before writing again. The value I used was 142 ms, I think. Your Mileage May Vary.
There is also a way to do some error handling that I did not try to utilize. Instead of the process crashing, there is a way to tell it to wait if this error is returned. That might be the best way for me to implement what I wanted to do, but I was assigned another task before I tried to get that to work.
There is a timing element in ncWriteMult's documentation I didn't look into very much, but that would space the frames out and could send 1,000 frames a second evenly distributed, instead of sending them as quickly as possible, wait some ms then send another batch.
If anyone could link us, or provide some code snippets of the error handling, or proper usage of ncGetAttribue, or some way to read faster, that would be greatly appreciated.

Console reporting webkit having hundreds of wakeups per second

I have been noticing frequent computer slowdowns on my 2011 MacBook Pro, always fully patched.
Checking Console, I found dozens of reports from Webkit saying things like "140 wake ups per second for 194 seconds"
I think these are related!!! Can someone tell me how to resolve this

Hello Antonio,
This forum is used to discuss and ask questions about .NET Framework Base Classes (BCL) such as Collections, I/O, Regigistry, Globalization, Reflection. Also discuss all the other Microsoft libraries that are built on or extend the .NET Framework, including
Managed Extensibility Framework (MEF), Charting Controls, CardSpace, Windows Identity Foundation (WIF), Point of Sale (POS), Transactions.
It seems your issue is more regarding Web Application issue, I suggest you posting it to:
http://forums.iis.net/1158.aspx
And you can check this article which may be helpful:
http://aspalliance.com/1184_Avoiding_Blocking_Issues_in_ASPNET_Session_State_Databases
Thanks for understanding.
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How can I find the number of megabytes per seconde of mij connection with internet

In a tuning program is asked the number of MB per second of mij lan-connection with internet.
I should like to know how I can find that number.

Hey Tongo,
This isn't really a Firefox question. I would suggest doing a quick Google search for "Internet Speed Test" or something of that nature. I know a very popular one is located here: http://www.speakeasy.net/speedtest/
Hopefully this helps!

Calculating value per second

Hi all. I need to just calculate and save the values per second in the variable that how many times per second a variable is being revieved in the method as a parameter and then show that progress as int / second in the progress bar
public void method(int a)
//Want to calculate [integer variable a] coming in the method per second
Thanks n Regards

We used to do this in C by declaring the variable as static... I've not tried it in Java:
public int myMethod(){
static i = 0;
i++;
return i;
}Since the Statics are only initialize at runtile the first line is only done once, not every entry--so you get an entry count.
you can also do this:
public void myMethod(){
myEntryCount++;where you have myEntryCount defined globally with respect to your method--like a class variable.

Logical reads per second

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