the DDOS starts exactly to the moment of the big price movement?? (right now)
That is exactly what I pointed out too:
It seems like you guys at Kraken can't handle the volume lately...
However, Kraken claims that the trade volume and this problem are not related.
I am not sure what to believe.
I don't believe there are DDoS atacks. The 'DDoS' attacks, as Serpens66 pointed out, always coincide with strong price movements. Kraken's customers can't take advantage of obvious trading and arbitrage opportunities. Usually this is unmistakable sign of insider manipulating profit taking and margin liquidation price levels.