I use Wordpress, and I asked the support team and they totd me:
Lock your site caused by a high load on the CPU:
"Date cpu_user cpu_sys cpu_procentc
=== === === === === ===
2016-07-25 4297 356 5
2016-07-26 7673 633 10
2016-07-27 7543 625 9
2016-07-28 18746 1621 24
2016-07-29 16946 1451 21
2016-07-30 15035 1255 19
Date: 2016-7-31
============
997 queries -
515 queries -
463 queries -
431 queries -
405 queries -
2237 queries - => "Mozilla/5.0 (iPhone; CPU iPhone OS 9_3_2 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Version/9.0 Mobile/13F69 Safari/601.1"
1218 queries - => "Mozilla/5.0 (Linux; Android 5.1.1; SAMSUNG SM-J700H Build/LMY48B) AppleWebKit/537.36 (KHTML, like Gecko) SamsungBrowser/3.3 Chrome/38.0.2125.102 Mobile Safari/537.36"
1063 queries => "Mozilla/5.0 (iPhone; CPU iPhone OS 9_3_3 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Version/9.0 Mobile/13G34 Safari/601.1"
1000 queries - "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"
577 queries - => "Mozilla/5.0 (iPhone; CPU iPhone OS 9_3_1 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Version/9.0 Mobile/13E238 Safari/601.1"
We recommended to optimize the work scripts of site or consider the option of switching to the VPS/Dedicated server:"
SO I dont think that was a ddos attack, bcz some device was Iphone!
I bought a VPS now