Re: pg_upgrade and statistics

Bruce Momjian <bruce@momjian.us> wrote:
> On Tue, Mar 13, 2012 at 01:18:58PM -0500, Kevin Grittner wrote:
 
>> cir=# analyze "CaseHist";
>> ANALYZE
>> Time: 143450.467 ms
>> cir=# select relpages, reltuples from pg_class where relname =
>> 'CaseHist';
>>  relpages |  reltuples  
>> ----------+-------------
>>   3588659 | 2.12391e+08
>> (1 row)
>>  
>> Either way, there are about 500 tables in the database.
> 
> That is 2.5 minutes.  How large is that database?
 
cir=# select pg_size_pretty(pg_database_size('cir'));
 pg_size_pretty 
----------------
 2563 GB
(1 row)
 
In case you meant "How large is that table that took 2.5 minutes to
analyze?":
 
cir=# select pg_size_pretty(pg_total_relation_size('"CaseHist"'));
 pg_size_pretty 
----------------
 44 GB
(1 row)
 
I've started a database analyze, to see how long that takes.  Even
if each table took 1/4 second (like on the small database) with over
500 user tables, plus the system tables, it'd be 15 minutes.  I'm
guessing it'll run over an hour, but I haven't timed it lately, so
-- we'll see.
 
-Kevin