Thigs to be considered before big import.

** Do Import process off times.
• Pass the values directly from source . Don't create any GUID or any column value in the import process.
• Increase the size of the CRM database to big enough to avoid the size increments
• Stop the backup jobs on the server
• Try to put the Data files, Log files and Backup up files on different drives
• Rebuild the indexes and Pad them up to 50% (Because it's a write operation)
• Disable all the organizations
• Put the batch size of 50000 in the SSIS