**Is your feature request related to a problem?** To improve IO performance as mentioned in #1175 and #1176 **Describe the solution you'd like** Using `libcurl-multi` instead of invoking threads for `HttpClient`. **Additional context** + https://curl.se/libcurl/c/libcurl-multi.html + https://curl.se/libcurl/c/multi-double.html