title: SQL Server stops responding
body: <p>I work on a database where we store sales of about 300 stores. There is 1 table per store and the total amount of lines is about 120 million (4 million for the biggest table).</p>
  
  <p>The machine is a windows server 2008 R2 on a citrix virtual machine with 65Gb memory and SQL Server version is 2014.</p>
  
  <p>Lines are added from the stores to the database via a webservice every minute so that customers (the store ownsers) can view their stats almost almost in real time.</p>
  
  <p>Christmas is close and the amount of sales per day is increasing, it is now something like 100k lines per day.</p>
  
  <p>The monitor says there is about 100-200 queries per second, they are all before their statistics and therefore query a lot of data.</p>
  
  <p>Database I/O says about 0.1Mb/s ~ 0.5Mb/s.</p>
  
  <p>CPU goes from 10% to 50%.</p>
  
  <p>Often, the database server stop responding (no more connection possible) for about 30 sec ~ 2 min and I don't know why.</p>
  
  <p>Is there any way I can find out why ?
  Should I upsize or do something else ?
  As data is not relational at all, may I go to a nosql solution for better availability ?</p>