The tuning tag has no wiki summary.
0
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0answers
62 views
InnoDB tuning with 1G of ram limit
I am trying to calculate variable moving averages crossover with variable dates.
That is: I want to prompt the user for 3 values and 1 option. The input is through a web front end so I can build/edit ...
0
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0answers
27 views
mysql: how many disk seeks were made for a select query
I will fire a select query. I want to know how many disk seeks does that query take.
mysql documentation has given formula for full table scan. ...
4
votes
2answers
159 views
How to Correctly Estimate the Average Number of I/O Operations my RAID 10 disk can offer?
The average Input/Output Operations per Second a disk can sustain is a very important factor in the tuning of MySQL / InnoDB databases, as it drives the speed with which Dirty InnoDB Buffer Pool pages ...
0
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0answers
50 views
PostgreSQL can't start after tuning some options
I'm having some issues with "too many clients" and I tried to change the max_connections param (currently 100). I tried to set some value like 300, but when I restart the service, I got this
...
1
vote
1answer
99 views
Slow queries to remote PostgreSQL db
I am running a Drupal site that is backed by Postgres. This is my first time running something with Postgres; I come from the MySQL world.
For doing dev work on the site, I connect to a VPN and ...
1
vote
1answer
151 views
MySQL 5.5 - determining correct write[read]_io_threads on high-end system?
Specifically dual-CPU 32 core - 128RAM - RAID 10 SSD . Ubuntu 64 server.
Heavy Innodb load at times - ~ 2000+ queries per sec. Heavy read and write.
Currently we are running on the default ...
2
votes
1answer
502 views
MySQL 5.5 - Innodb - innodb_log_file_size higher than 4GB combined?
When reading online about innodb_log_file_size, it says
The combined size of the log files must be less than 4GB
So what happens if it needs to be larger?
In books and online, it says to set ...
0
votes
1answer
670 views
Mysql 5.5: Optimizing all tables with mysqlcheck - is it useful to run the -check option along with -optimize?
I plan on running 'mysqlcheck --optimize --all-databases' to clear up some fragmentation.
Would it be useful to run -check with this option or does the -optimize already take care of that?
I am only ...
1
vote
1answer
51 views
tuning feed item's table query with multiple condition
I have a query like this:
SELECT *
FROM `rss_item`
WHERE `feed_id` = 1 and `timestamp` < 1350698635
ORDER BY `rss_item`.`timestamp` ASC
MySQL: 5.1; table engine: innodb
Explain result:
...
0
votes
2answers
168 views
Tuning query to remove joins for reporting
This is the query I was sent. There is currently no data in the system as I was converting this query from teradata to SQL server.
SELECT user_id FROM user_table
LEFT OUTER JOIN
(
SELECT user_id , ...
0
votes
0answers
247 views
Oracle 10g - Sudden change in execution time for specific query
After the DBAs fiddled with some parameters in our Oracle 10g Production Environment, most queries became a little faster. But a single query (a quite complex one) became dramaticaly slower - it went ...
1
vote
1answer
466 views
InnoDB Performance Tuning
I'm new to database administration so please excuse any omissions of what would seem like basic info to provide for this problem.
I'm a RoR developer and our team is currently short a DBA, so we're ...
5
votes
2answers
242 views
What can I do to speed up this SQL Query?
I've created this SQL query with the help of @Dems :-)
Here is some detail, I tried to make a SQLFiddle but I kept getting errors with my variables... This works in Sql Server 2008... My question ...
2
votes
2answers
658 views
MySQL 5.1.63 - using tuning-primer - Table Cache question
tuning_primer says the following:
TABLE CACHE
Current table_open_cache = 812 tables
Current table_definition_cache = 256 tables
You have a total of 498 tables
You have 812 open tables.
Current ...
4
votes
2answers
730 views
How I should fix the following update statement to make it run faster?
I have the following DML:
UPDATE rc_usutb011 u
SET cod_ant=(
SELECT cod_hst
FROM rc_pdptb101 p
WHERE ocip_hst=ocip_ant
AND p.sector=u.sector
);
The explain plan ...
