c++ - Memory consumption during parsing of YAML with yaml-cpp -


i developing qt application embedded system limited memory. need receive few megabytes of json data , parse fast possible , without using memory.

i thinking using streams:

json source (http client) ---> zip decompressor ---> yaml parser ----> objects mapped database

data arrive network slower can parse it.

  1. how memory yaml-cpp need parse 1mb of data?
  2. i parsed raw data decompressor , internal memory used data yaml parser released object mapped database created. possible?
  3. does yaml-cpp support asynchronous parsing? json object parsed, can store in database without waiting full content http source.

since have memory constraints , data in json, should use low-memory json parser instead of yaml parser. try jsoncpp - although i'm not sure support streaming (since json doesn't have concept of documents).

yaml-cpp is designed streaming, won't block if there documents parse stream still open; however, there outstanding issue in yaml-cpp reads more single document @ time, isn't designed extremely low memory usage.

as how memory takes parse 1 mb of data, on order of 3 mb (the raw input stream, plus parsed stream, plus resulting data structure), may vary dramatically depending on kind of data you're parsing.


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