[問題]
UnknownError: Failed to get convolution algorithm. This is probably because cuDNN failed to initialize, so try looking to see if a warning log message was printed above. [[{{node conv2d_1/convolution}}]] [[{{node metrics/acc/Mean}}]]

[解決案]
cudnnを、7.5.1.10-1にダウングレードすれば、正常に動きます。

[実行環境]
OS：archlinux(linux-lts)
GPU:RTX 2080
cuda：cuda 10.1.168-1
cudnn：7.5.1.10-1(7.6.0.64-1からdowngrade)
tensorflow：tensorflow-cuda 1.13.1-5