从github上取一个repo，它非常非常慢，我不知道为什么。

C:\projects>git clone --depth 1 git@github.com:sawilde/opencover.git
Cloning into 'opencover'...
The authenticity of host 'github.com (192.30.255.112)' can't be established.
RSA key fingerprint is SHA256:nThbg........................................
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'github.com,192.30.255.112' (RSA) to the list of known hosts.
remote: Enumerating objects: 1459, done.
remote: Counting objects: 100% (1459/1459), done.
remote: Compressing objects: 100% (829/829), done.
Receiving objects:  95% (1388/1459), 14.09 MiB | 8.00 KiB/s

我尝试了一些方法，例如。windows和ubuntu（通过windows子系统），full vs shallow clone，ssh vs https，...等，我得到同样的缓慢的行为; 30分钟到14 MB？我不记得有这么糟。
非常沮丧，因为我得到了良好的速度对一般的下载，不知道为什么它是如此缓慢的克隆一个回购。