Logging to one process from thousands: How does it work?

[Raimo Niskanen]

There is a small fix in the scheduler for the standard 
producer/consumer problem: A process that sends to a 
receiver having a large receive queue gets punished
with a large reduction (number of function calls)
count for the send operation, and will therefore
get smaller scheduling slots.

joelr1@REDACTED (Joel Reymont) writes:

> Folks,
> 
> I have just rewrote some code from Haskell to Erlang and there's one
> thing that baffles me.
> 
> I tried to approach Haskell the way I would code in Erlang and set up
> a logger thread with an unbounded message queue. I then launched a
> few hundred/thousand threads that traced to the logger periodically.
> This is no different than using disk_log in Erlang, I think.
> 
> The Haskell logger thread got quickly overwhelmed with messages I
> think. The queue build-up was huge. How does it work with Erlang? Is
> the scheduler specially tuned somehow to give different priorities to
> different threads? The Haskell scheduler, I believe, is just round-
> robin.
> 
> 	Thanks, Joel
> 
> --
> http://wagerlabs.com/
> 
> 
> 
> 
> 

-- 

/ Raimo Niskanen, Erlang/OTP, Ericsson AB