Virtual threads and File IO

[Pedro Lamarão]

Linux sendfile and Windows TransmitFile are very specific beasts.
If you are sending files to sockets, yes, that should be the best the
system can do.
For general file I/O in Linux, the API called AIO with aio_read and
aio_write is no good.
These communicate completion asynchronously via UNIX signals.
Linux I/O rings seem to be the way forward, but do not seem ready for
general production yet.
Some cloud providers disable it because of a history of security bugs.
Pedro.

Em seg., 3 de jun. de 2024 às 11:06, Robert Engels <robaho at icloud.com>
escreveu:

> Here is an interesting case study on async file IO under Linux
> http://blog.lighttpd.net/articles/2006/11/12/lighty-1-5-0-and-linux-aio/
>
> > On May 31, 2024, at 6:22 PM, robert engels <robaho at icloud.com> wrote:
> >
> > I looked into the code. Seems Java is the same. I looked into it - and
> seems for many workloads async file IO can improve efficiency by 80%.
> >
> >> On May 31, 2024, at 5:45 PM, Robert Engels <robaho at me.com> wrote:
> >>
> >> Hi,
> >>
> >> An interesting question came up on the Go support channels. One of the
> principle engineers stated that for local file IO, the Go routine (similar
> to virtual thread) won’t release the carrier thread.
> >>
> >> Is this the same with Java virtual threads? Yes, local IO is typically
> fast - but it is still order of magnitudes slower than memory computations
> - which the virtual thread could be doing while waiting for the IO request
> to be serviced.
> >>
> >> R
>
>
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