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Systemcopy using R3load - Index creation VERY slow

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We exported a BW 7.0 system using R3load (newest tools and SMIGR_CREATE_DDL) and now importing it into the target system.

 

Source database size is ~ 800 GB.

 

The export was running a bit more than 20 hours using 16 parallel processes. The import is still running with the last R3load process. Checking the logs I found out that it's creating indexes on various tables:

 

(DB) INFO: /BI0/F0TCT_C02~150 created#20100423052851
(DB) INFO: /BIC/B0000530000KE created#20100423071501
(DB) INFO: /BI0/F0COPC_C08~01 created#20100423072742
(DB) INFO: /BI0/F0COPC_C08~04 created#20100423073954
(DB) INFO: /BI0/F0COPC_C08~05 created#20100423075156
(DB) INFO: /BI0/F0COPC_C08~06 created#20100423080436
(DB) INFO: /BI0/F0COPC_C08~07 created#20100423081948
(DB) INFO: /BI0/F0COPC_C08~08 created#20100423083258
(DB) INFO: /BIC/B0000533000KE created#20100423101009
(DB) INFO: /BIC/AODS_FA00~010 created#20100423121754

 

As one can see on the timestamps the creation of one index can take an hour or more.

 

x_cons is showing constant CrIndex reading in parallel, however, the througput is not more than 1 - 2 MB/sec.  Those index creation processes are running now since over two days (> 48 hours) and since the .TSK files don't mentioned those indexes any more I wonder how many of them are to be created and how long this will take.

 

The whole import was started at "2010-04-20 12:19:08" (according to import_monitor.log) so running now since more than three days with four parallel processes. Target machine has 4 CPUs and 16 GB RAM (CACHE_SIZE is 10 GB). The machine is idling though with 98 - 99 %.

 

I have three questions:

 

- why does index creation take such a long time? I'm aware of the fact, that the cache may not be big enough to take all the data but that speed is far from being acceptable. Doing a Unicode migration, even in parallel, will lead to a downtime that may not be acceptable by the business.

 

- why are the indexes not created first and then filled with the data? Each savepoint may take longer but I don't think that it will take that long.

 

- how to find out which indexes are still to be created and how to estimate the avg. runtime of that?

 

 

 

Markus


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