Re: Uber migrated from Postgres to MySQL

Condor <condor@stz-bg.com> writes:

> On 26-07-2016 21:04, Dorian Hoxha wrote:
>
>> Many comments: https://news.ycombinator.com/item?id=12166585
>> https://www.reddit.com/r/programming/comments/4uph84/why_uber_engineering_switched_from_postgres_to/
>>
>> On Tue, Jul 26, 2016 at 7:39 PM, Guyren Howe <guyren@gmail.com> wrote:
>>
>>> Honestly, I've never heard of anyone doing that. But it sounds like
>>> they had good reasons.
>>>
>>> https://eng.uber.com/mysql-migration/
>>>
>>> Thoughts?
>>>
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>
>
> They are right for upgrades.
> It's a hard to shutdown 1 TB database and wait couple of days
> pg_upgrade to finish upgrade and meanwhile database is offline.
> In some distros after upgrade of PG version you don't have old binary
> and library, need to do full dump and restore that take time and disk
> space.

Yeah, very hard indeed when done by unskilled DBAs :-)

I've done several ~7TB pg_upgrades and with the hard link option and a
framework that parallelizes the post-analyzer phase...

...45 minutes till completion.


>
> Regards,
> Hristo S.

--
Jerry Sievers
Postgres DBA/Development Consulting
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