anchor.diff:  Just as in <<docs-update,Update API>> you can set `ctx.op` to change the
   operation that is executed:
   
  -
  +[horizontal]
   `noop`::
   
   Set `ctx.op = "noop"` if your script decides that it doesn't have to make any
  
positive.code: wait_time = target_time - write_time = 2 seconds - .5 seconds = 1.5 seconds
  --------------------------------------------------
  
  Since the batch is issued as a single `_bulk` request large batch sizes will
  cause Elasticsearch to create many requests and then wait for a while before
  starting the next set. This is "bursty" instead of "smooth". The default is `-1`.
  
  
negative.code: [[docs-update-by-query-automatic-slice]]
  ==== Automatic slicing
  
  You can also let update by query automatically parallelize using
  <<sliced-scroll>> to slice on `_uid`. Use `slices` to specify the number of
  slices to use:
  
  