using dbt2 postgresql 8.4 - rampup time issue - Mailing list pgsql-performance

Hi,

We are using dbt2 to check performance of postgresql 8.4 on Linux64 machine. When we increase "TERMINALS PER WAREHOUSE" TPM value increase rapidly but rampup time increase too , dbt2 estimated rampup time calculation do not work properly that’s why it run the test for wrong duration i.e.

1.
Settings :
    DATABASE CONNECTIONS: 50
    TERMINALS PER WAREHOUSE: 10
    SCALE FACTOR (WAREHOUSES): 200
    DURATION OF TEST (in sec): 7200
Result :
                             Response Time (s)
     Transaction      %    Average :    90th %        Total        Rollbacks      %
    ------------  -----  ---------------------  -----------  ---------------  -----
        Delivery   3.96      0.285 :     0.023        26883                0   0.00
       New Order  45.26      0.360 :     0.010       307335             3082   1.01
    Order Status   3.98      0.238 :     0.003        27059                0   0.00
         Payment  42.82      0.233 :     0.003       290802                0   0.00
     Stock Level   3.97      0.245 :     0.002        26970                0   0.00
    ------------  -----  ---------------------  -----------  ---------------  -----
    
    2508.36 new-order transactions per minute (NOTPM)
    120.1 minute duration
    0 total unknown errors
    2000 second(s) ramping up

2.
Settings :
    DATABASE CONNECTIONS: 50
    TERMINALS PER WAREHOUSE: 40
    SCALE FACTOR (WAREHOUSES): 200
    DURATION OF TEST (in sec): 7200
Result :
                             Response Time (s)
     Transaction      %    Average :    90th %        Total        Rollbacks      %
    ------------  -----  ---------------------  -----------  ---------------  -----
        Delivery   3.95      8.123 :     4.605        43672                0   0.00
       New Order  45.19     12.205 :     2.563       499356             4933   1.00
    Order Status   4.00      7.385 :     3.314        44175                0   0.00
         Payment  42.89      7.221 :     1.920       473912                0   0.00
     Stock Level   3.97      7.093 :     1.887        43868                0   0.00
    ------------  -----  ---------------------  -----------  ---------------  -----
    
    7009.40 new-order transactions per minute (NOTPM)
    69.8 minute duration
    0 total unknown errors
    8016 second(s) ramping up
3.
Settings :
    DATABASE CONNECTIONS: 50
    TERMINALS PER WAREHOUSE: 40
    SCALE FACTOR (WAREHOUSES): 200
    DURATION OF TEST (in sec): 7200
Result :
                             Response Time (s)
     Transaction      %    Average :    90th %        Total        Rollbacks      %
    ------------  -----  ---------------------  -----------  ---------------  -----
        Delivery   3.98      9.095 :    16.103        15234                0   0.00
       New Order  45.33      7.896 :    14.794       173539             1661   0.97
    Order Status   3.96      8.165 :    13.989        15156                0   0.00
         Payment  42.76      7.295 :    12.470       163726                0   0.00
     Stock Level   3.97      7.198 :    12.520        15198                0   0.00
    ------------  -----  ---------------------  -----------  ---------------  -----
    
    10432.09 new-order transactions per minute (NOTPM)
    16.3 minute duration
    0 total unknown errors
    11227 second(s) ramping up
    
These results show that dbt2 test actually did not run for 2 hours but it start varying with the increase of  "TERMINALS PER WAREHOUSE" value i.e. 1st Run ( 120.1 minute duration ), 2nd Run (69.8 minute duration) and 3rd Run (16.3 minute duration).

To fix and sync with the rampup time, I have made a minor change in the dbt2-run-workload script i.e.

    --- dbt2-run-workload      2010-07-02 08:18:06.000000000 -0400
    +++ dbt2-run-workload   2010-07-02 08:20:11.000000000 -0400
    @@ -625,7 +625,11 @@
     done
    
     echo -n "estimated rampup time: "
    -do_sleep $SLEEP_RAMPUP
    +#do_sleep $SLEEP_RAMPUP
    +while ! grep START ${DRIVER_OUTPUT_DIR}/*/mix.log ; do
    +       sleep 1
    +done
    +date
     echo "estimated rampup time has elapsed"
    
     # Clear the readprofile data after the driver ramps up.
 
What is rempup time ? And what do you think about the patch?. Can you please guide me?. Thanks.

Best Regards,
Asif Naeem

---

Hotmail: Trusted email with Microsoft’s powerful SPAM protection. Sign up now.