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1.   Xray provides some specific custom fields that calculate their values on the fly. This means that you should have that in mind, specially if you're including them in tables/issue listings/gadgets.
   1. The most intensive custom fields are the "Test Execution Defects" and the "Test Set Status" (isto ja nao é verdade, certo Diamantino Campos? há aqui algum custom field calculado em realtime a salientar?).  The => não é verdade no caso de já estarem calculados. O Test Set Status é muito mau, é de evitar o seu uso. The "Tests Count", as it does an aggregation, also is intensive if you use it for multiple issues.

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1.  Xray provides some maintenance operations that can be used under certain circumstances, if needed. If you clear some of Xray calculated custom fields, either using Integrity Checker > Calculated Custom Field Values option in administration settings or using the available bulk operations for Requirement Status and TestRunStatus custom fields, it will impact the reindex time considerable as the values have to be all recalculated. 
2. Diamantino Campos haverá algum custom field que possa ser excluido do reindex e que afecte o tempo de reindex dramaticamente? => não, pq o requirements status é necessário para o funcionamento do Xray

Other operations

1.  Avoid bulk cloning Test plans or Test Executions using some specific apps for that purpose; cloning multiple issues at the same time can add some overhead to Jira as these can affect the calculations of the statuses of Tests and requirements.

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