Re: Changing SEMVMX to a tunable parameter

[Manfred Spraul (manfred@colorfullife.com)]

Arvind Kandhare wrote:

> >>How?
> > > SEMVMX is right now 32k, because the value is stored in an signed
> > > short,
> > > both internally and in the SuSv2 ABI.
>
>
> semval is a part of struct sem and it is an integer as of now (2.5.69).
> That is, it doesn't comply with SuS v3 as far as data type is concerned.
>
> SuS v3 specifies semval to be an unsigned short.i.e. we can have a 
> maximum of 64K on this.

Ok, thus you want to increase it from 32k to 64k, but not beyond, correct?
You'd have to check that there are no hidden signed/unsigned assumptions 
in ipc/sem.c

> Irrespective of the maximum value, an option to tune this limit would be
> highly desirable.

_If_ there are no signed/unsigned problems and if Oracle wants 64K, then 
I would increase SEMVMX to 64K, without making it tunable. Dito for SEMAEM.

--
   Manfred

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