What happened internally on Scroll type of search, it looks like it will block the "Merge" process, since ES needs to keep the context of the scroll for a shard, correct?
I've heard someone told me that the scroll will blocks the "refresh" option of the index, which seemed to be odd to me.
The only thing related I got from the doc is https://www.elastic.co/guide/en/elasticsearch/reference/2.3/search-request-scroll.html#scroll-search-context
which means any open search context will ONLY blocking deleting the "old" segments, which makes more sense to me, since the search context may refers to these "old" segments to get the data.
Can someone explains me more about the scroll internally in ES?