Sharepoint Crawl schedule

The sharepoint uses a crawl schedule to index the files uploaded, by default, this crawl task run every 5 minutes.
If you have the SharePoint Database on a shared server, maybe the performance is down, because this task use the HDD.

To avoid this, you can change the Schedule, going to the Central Administration -> Operations -> Services on Server -> Windows Sharepoint Services Search, and modifiying the Indexing Schedule.