after i restored database and website i test my site on webpagetest first byte very slow it was fast before anyone know why
Time to First Byte: 8197 ms
my site : http://eliteshoutouts.com/
Can you make direct access to the database for the query that generates home page? You should be able to run this multiple times and measure the response times. If that has shot up, then it is the place to debug. WPT will not really be able to tell anything much apart from the fact that your server is taking a lot of time to respond for the very first request.
Yes, it will be. There’s decades of experience gone in to making data access fast - it’s not just reading data from disk.
There are a multitude of caches which store your data in memory, so that the second time you ask for the same bit of data, it’s ready to pass straight back - no disk access necessary. It’s the loading of these caches that it taking the time. You may also have similar caches for php ( eg opcode cache ), the web server ( eg open file cache ) and the CMS ( eg full page cache ), all attempting to short-circuit the process of building your web page.
Once you’ve repopulated them ( assuming they’re big enough ), performance will improve.