How to adjust HPACK dynamic table?

[Jon Carmicheal]

I would like to disable the caching of headers in the dynamic table of the HTTP/2 HPACK compression algorithm described in RFC 7541. I have defined my nginx server with

listen 8080

http2

;

and I've confirmed that the HPACK algorithm is working as expected with Huffman encoding, static header table indexing, and dynamic header table indexing. But I haven't been able to disable the dynamic table.

RFC 7541 mentions in "Section 4.2. Maximum Table Size" the ability of an HTTP/2 node to "clear entries from the dynamic table by setting a maximum size of 0, which can subsequently be restored." Is that a feature supported by nginx? Can I disable the dynamic table entirely so that no header fields are cached? And can I arbitrarily send a flush request so that all entries are evicted and then the dynamic table size is restored? If so, how?

I've been trying to play with "http2_max_field_size" and "http2_max_header_size" in the server configuration file as described in https://nginx.org/en/docs/http/ngx_http_v2_module.html. But I don't think those are the right parameters. When I set either of them to zero, it makes the server return an error when a header is sent.

Thanks for any pointers you can give me.
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