1
vote
1answer
659 views

PostgreSQL: performance descrease due to index bloatper

I'm running a PgSQL 8.1 on a CentOS 4.4 system (not upgradable unfortunately). There's a Java app running on top of the PgSQL daemon and we got to reindex the database every 2 months or so. Also ...
4
votes
2answers
2k views

Why is dropping an index on MyISAM table so slow?

Why is dropping an index on MyISAM table so slow? I can't imagine I'd have social network with 700m records & dropping index. There are only one-column indexes, all of them are fulltext (I need ...
2
votes
4answers
3k views

How to reduce mysql disk io?

mysql> explain SELECT * -> FROM (`items`) -> WHERE `states` = 'A' -> ORDER BY `updated_date` desc -> LIMIT 20520, 40; ...
0
votes
2answers
201 views

Sphinx indexer slows down the database: How to give it low priority?

All my tables use InnoDB, and I have set sphinx sql_range_step to the minimum, which is 128. This improved the performance a lot, but it is still very slow if you make a request right after a new step ...
0
votes
1answer
124 views

Which is faster, key_cache or OS cache?

In a tb with 1 mil. rows if I do (after I restart the computer - so nothing it's cached): 1. SELECT price,city,state FROM tb1 WHERE zipId=13458; the result is 23rows in 0.270s after I run 'LOAD ...
0
votes
1answer
1k views

Optimum size for ISA server disk cache

Our ISA server administrator is saying this: How the ISA cache works is as follows: when the ISA server receives a request to access a website, the first step it takes is check through the ...
3
votes
1answer
860 views

Why won't SQL Server use an index seek when running a parameterized query?

When I execute the following query in SQL Server 2005 it uses an index seek, as verified by viewing the execution plan. SELECT * FROM Account WHERE Number = '123456789' But when I run the same ...