Re: Re: BUG #12990: Missing pg_multixact/members files (appears to have wrapped, then truncated)

On Tue, May 5, 2015 at 6:36 PM, Kevin Grittner <kgrittn@ymail.com> wrote:
>> So I think that
>> some_constant should be at least 2, if we try to do it this way, in
>> other words if you set the GUC for 10% of offset space, we also start
>> triggering wraparounds at 20% of member space.
>
> But what if they configure it to start at 80% (which I *have* seen
> people do)?

I might be confused here, but the upper limit for
autovacuum_multixact_freeze_max_age is 2 billion, so I don't think
this can ever be higher than 50%. Well, 46.5%, really, since 2^32 > 4
billion.  autovacuum_freeze_max_age is similarly limited.

--
Robert Haas
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