Re: [HACKERS] Why must -N be >= 16?

The Hermit Hacker <scrappy@hub.org> writes:
> Just trying to start up a 'mini-process' of -B 8 -N 4, and it tells me
> that -N  must be >= 16 ... why?  

You misread it --- -N can be as small as you like, but we don't allow
a really tiny -B.  To quote the code:
   if (NBuffers < 2 * MaxBackends || NBuffers < 16)   {       /* Do not accept -B so small that backends are likely to
starvefor        * lack of buffers.  The specific choices here are somewhat arbitrary.        */       fprintf(stderr,
"%s:-B must be at least twice -N and at least 16.\n",               progname);       exit(1);   }
 

I'm not even real sure that -B 16 is going to work well if you throw
complex queries at it --- we've not stressed the system with small
numbers of buffers.
        regards, tom lane