Error when pushing: Connection closed before message completed

[ettom]

When pushing many paths at once, attic push often fails with:

Error: error sending request for url (http://127.0.0.1:8180/_api/v1/upload-path)

Caused by:
    0: client error (SendRequest)
    1: connection closed before message completed

This happens regardless of whether a reverse proxy is used or not. It seems especially prevalent if --ignore-upstream-cache-filter is used (probably due to it increasing the amount of uploads dramatically). I can very reliably reproduce it by pushing the ./result of my NixOS build into a fresh cache with --ignore-upstream-cache-filter.

Looks like this is the same issue: hyperium/hyper#2136, mentioned in many other issues and PRs.

I guess in the case of attic, disabling pooling on the client side would be undesirable and it would be better to implement a retry mechanism, at least for this specific error?