Re: [Question] [Block] Is there a way to control the read caching of a block device?

[DUO Labs]

I found that dd could do the same thing with `dd of=ofile oflag=nocache 
conv=notrunc,fdatasync count=0` --- looking at the source code led me to 
posix_fadvise --- I did try it before, but gave up on it because it didn't seem 
to be working. It turns out that both the offset and length need to be 
page-aligned --- passing in the entire range worked perfectly fine.

I have looked at virtio-fs, but there's no support for macOS hosts (at least, 
not until that patch enabling vhost-user support for non-Linux platforms is 
merged in. However, even then, there will need to be extra work adding support 
in rust-vmm, as right now, the code is very specific for Linux).