[erlang-questions] halfword emulator state

Attila Rajmund Nohl <>
Tue May 31 10:48:48 CEST 2011

2011/5/30, Paolo Negri <>:
> Dear list
> I would like to assess the state of development and recommended usage
> of the halfword emulator.
> Apart from the initial announcement [1] and the fixes/improvements
> introduced with R14B03 [2] there hasn't been much discussion about it.
> As we're evaluating the use of the halfword emulator in production I
> would like to ask questions.
> - Is anyone already using the halfword emulator in production
> environments, if yes, are what are the experiences, is it stable, what
> are the effective gains, is there any measurable overhead?

We've had some emulator crashes on R14B02 (since fixed in R14B03), so
I definitely not advise the halfword emulator in R14B02. Apart from
this bug it was quite stable. Unfortunately it turned out that some of
our Erlang processes use a lot more memory than we expected, so due to
the 4GB limit for process memory we couldn't decrease the number of
running Erlang VMs, that's why we stayed with the 32 bit emulator
currently. We'll have an other go with R14B03.

More information about the erlang-questions mailing list