preload is heavy load on server

I use wordpress super cache and as u know we can use preload option to cache almost all pages before visitors click on any pages.. problem is by 1000 pages to preload cache, it takes one hour pressure time on mysql, and some visitors during this one hour get bounced (out of memory or something..). my question is: isn’t there a way we could have like 30 second wait between every page durin preload cache? so when preload starts to auto cache 30 sec. waits before starting next page to cache. then visitors and bots won’t get bounced during preload time.. it shouldn’t be impossible there must be a script code to do that, but i don’t know their naming system.. it must go like maximum number or threads or pages to cache at the same time or like number of sec. between each page cache.. please don’t offer to use another plugin that’s another headache to get used to the new one.. here is my site: brand-bartar.ir

https://wordpress.org/plugins/wp-super-cache/