[erlang-bugs] hipe_mfait_lock

[Louis-Philippe Gauthier]

Hi Sverker,
That's not a bad idea, I'll try that approach!

Thanks,
LP

On Thu, Jan 15, 2015 at 12:27 AM, Sverker Eriksson <
sverker.eriksson@REDACTED> wrote:

>  One quite simple improvement is to change the hipe_mfait_lock to be a
> read-write mutex (erts_smp_rwmtx_t).
> And then do read-lock at lookup and exclusive write-lock only when
> inserting a new entry in the table.
>
> I don't think that requires much knowledge about the VM to pull off ;-) .
>
> /Sverker, Erlang/OTP
>
>
>
>
> On 01/14/2015 12:34 AM, Louis-Philippe Gauthier wrote:
>
> Hi erlang-bugs,
> I couple of months ago I tried running our full application using HiPE. I
> ran into several issues, some manageable, some not... The most problematic
> issue was due to locking, specifically, the hipe_mfait_lock (you can see
> the lock counter output in the gist bellow).
> https://gist.github.com/lpgauth/2b3220f4bceeed6f62d0
>
> Looking at the code it's obvious that this is a known problem... the
> following comment was added when the lock was added in 2010.
>
> "XXX: Redesign apply et al to avoid those updates."https://github.com/erlang/otp/blob/maint/erts/emulator/hipe/hipe_bif0.c#L1218
>
> Unfortunately, I'm don't know the runtime enough to start patching it... so
> instead I'm reporting it.
>
> Thanks,
> LP
>
>
>
>
> _______________________________________________
> erlang-bugs mailing listerlang-bugs@REDACTED://erlang.org/mailman/listinfo/erlang-bugs
>
>
>
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