On macOS, when calling `spawn`, the child process's stdio buffer
size is 8192 bytes. This is due to the AF_UNIX socket buffer size
being 8192 bytes in the XNU kernel.
When large amounts of data are transferred through the child
process's stdio, this buffer size can cause performance issues.
To mitigate this, the buffer size has been increased to 65536
bytes, aligning it with the behavior on Linux.
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