[tahoe-dev] Observations on Tahoe performance

[Sam Mason]

On Wed, Aug 26, 2009 at 05:00:24PM -0700, Brian Warner wrote:
> I think it's another example of asynchronous interfaces being such a
> different approach that they really want all the code around them to be
> async too. It's awfully hard to mix sync and async code in the same
> program, and most programs are synchronous, so the async fileio code has
> a tough time getting acceptance, so it never really gets improved/fixed/etc.

I thought it was mostly a kernel complexity issue; filesystem code tends
to rely on the process's kernel stack to keep track of how its getting
on and when things go async you have to start dynamically allocating the
stack--this gets fiddly.  I think this is what was going on a few years
ago in Linux when I last looked at it, maybe things have moved on now?

-- 
  Sam  http://samason.me.uk/