contramundum53

@toshihikoyanase Could you review this PR?

This seems to be solved in #3510. We will close this issue.

How is this different from sampling one at a time?

How about using named pipes instead? It might be easier.

In Unix the following Python code using anonymous pipes works. ``` import os import subprocess pipes = [os.pipe() for i in range(3)] for r,w in pipes: os.set_inheritable(w, True) subp =...

https://docs.rs/os_pipe/latest/os_pipe/ seems to be a cross-platform library for handling pipe creation. Also, it seems that in Rust all file descriptors are inherited by the child process.

There has been some discussions and more TODOs have been found. We will close this issue.

Since what internal states a `Sampler` computes belongs to the realm of implementation details, an additional feature / a simple refactoring of a `Sampler` could change the necessary internal states....

I made an early prototype of TPE visualization. The following GIFs compare the effect of `consider_magic_clip` option in `TPESampler`. (Other parameters are left to be default.) |`consider_magic_clip=True` | `consider_magic_clip=False` |...

The code for the above visualization is available [here](https://github.com/contramundum53/optuna-tpe-visualized).