Re: 9.1 to 9.2 requires a dump/reload?

On Tue, Oct 23, 2012 at 7:41 AM, Nikolas Everett <nik9000(at)gmail(dot)com> wrote:
> On Mon, Oct 22, 2012 at 6:17 PM, Alan Hodgson <ahodgson(at)simkin(dot)ca> wrote:
>>
>> On Monday, October 22, 2012 05:55:07 PM Nikolas Everett wrote:
>> > I see that pg_upgrade is an option. Having never used how long should I
>> > expect pg_upgrade to take? Obviously we'll measure it in our
>> > environment,
>> > but it'd be nice to have a ballpark figure.
>>
>> pg_upgrade using hard links should only take a minute or 2. You'll also
>> need
>> to shuffle around packages and services and config files. The slowest part
>> for any
>> decent sized database will be doing an analyze after bringing it up under
>> 9.2,
>> though. So however long that takes for your db, plus maybe 10-15 minutes
>> or
>> so, if you've practiced.
>
>
> Yikes! Analyze will certainly take the longest time - we'll have to build
> some kind of strategy for which tables to analyze first and how many to
> analyze at once.

Note that if you nearly zero downtime, then slony is really the only answer.