Re: BUG #3888: postmaster: misleading error message for illegal -B values

Marti Raudsepp wrote:
> Bug reference:      3888
> Logged by:          Marti Raudsepp
> Email address:      marti@juffo.org
> PostgreSQL version: 8.3RC1
> Operating system:   Linux AMD64
> Description:        postmaster: misleading error message for illegal -B
> values
> Details:
>
> When launching postmaster with a small -B (number of buffers) value, it
> reports the following error:
> "postmaster: the number of buffers (-B) must be at least twice the number of
> allowed connections (-N) and at least 16"
>
> However, as of PostgreSQL 8.3, postmaster requires that the number of
> buffers is at least (max_connections*2 + 6)

Hmm. The minimum is actually (max_connections + max_autovacuum_workers)
* 2. The default max_autovacuum_workers is 3, which is where that 6
(2*3) comes from.

--
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com