diff --git a/docs/Files/UserGuide/faq.rst b/docs/Files/UserGuide/faq.rst index 68c189c4c02193395be69617786c362cee2dd1fc..7a0adb79f31a158eb059eb225229c935daf8da87 100644 --- a/docs/Files/UserGuide/faq.rst +++ b/docs/Files/UserGuide/faq.rst @@ -63,6 +63,29 @@ Or use the replicate command in the :doc:`UserGuide/CommandReference/DataManagem See the list of available :ref:`storageelements` +How to stage files +`````````````````` + +If a Storage Element uses a tape back-end file access can be slow (e.g.: +CERN-SRM). To speed up the access the :ref:`storageelements` should be told +which files will be used. This is done via the +:doc:`AdministratorGuide/CommandReference/dirac-stager-stage-files` command. + +First obtain the list of files. Check on which Storage Element the files are +located by identifying available file replicas. This can be done for example +with the :doc:`UserGuide/CommandReference/DataManagement/dirac-dms-lfn-replicas` +command or in the :doc:`UserGuide/CommandReference/DataManagement/dirac-dms-filecatalog-cli`. Then issue the command. + +.. note:: + + The command will not give an error if wrong files or Storage Elements are + given as input. + +To see if files are being staged use **dirac-stager-monitor-file**. Once the +file has been staged the staging request is removed from the Database and this +command will return that the file has no staging request pending. + + Jobs ----