Delete All Posts Generated by this Plugin not works well

I have some issue and I want to " Delete All Posts Generated by this Plugin" After I click the button, and wait ,then it will cause A timeout occurred,  Error code 524 Also, if I click Top News to Post in the left menu, if will shows error <b>Fatal error</b>: Allowed memory size of 1073741824 bytes exhausted (tried to allocate 24576 bytes)