What is triple live index?

Does anyone know what the "triple live" index?

I am upgrading RTC server from version 4.0.5 to 6.0.2 in production server.
I ran ccm_upgrade.sh to upgrade RTC server then a reindex was proceeded in repotools-ccm.sh -addTables.
This reindex took much longer time than in test server.
There is a message indicating the number of "triple live" indexes and elapsed time.
It is 1 resource of the "triple live" index in testing, but 272322 resource in production.

I would like to know why the number of resources has increased.

Here is the result of the ccm_upgrade.sh.

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Step 1: Add tables


Directory /opt/IBM/JazzTeamServer602/server
Command:
     repotools-ccm.sh -addTables
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CRJZS6162I Updating indexes to include change of new resources.
CRJZS5654I The processing of 272322 resource of the "triple live" index of the special application ended in 25679621 mili seconds.
CRJZS5654I The processing of 1 resource of the "text live" index of the special application ended in 113 mili seconds.
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The ccm upgrade succeeded. You may now start the servers in your deployment.