database-tuning

I'm using SQL Server Profiler to figure out what process are consuming SQL process and I found that the event class Audit Logout is causing a huge number of reads and consume cpu process. Is it normal? Or do I have something wrong in the SQL Server configuration? The audit logout event aggregates a lot of its values like reads/writes, connection times, etc. from the time the connection was opened. See http://msdn.microsoft.com/en-us/library/ms175827.aspx - the definition for your specific question added here: Reads Number of logical read I/Os issued by the user during the connection. So

How do I profile a MySQL database. I want to see all the SQL being run against a database. I know you can do this: set profiling=1; Run your slow query (eg SELECT * FROM messages WHERE fromaddress='xxx'; SHOW PROFILES; But this seem to only apply to stuff run on the command line, I want to see the results from running a website. You want the query log - but obviously doing this on a heavy production server could be... unwise. Matija That worked for me on Ubuntu. Find and open your MySQL configuration file, usually /etc/mysql/my.cnf on Ubuntu. Look for the section that says “Logging and

I've been searching the web looking for best practices for configuring MongoOptions for the MongoDB Java driver and I haven't come up with much other than the API. This search started after I ran into the "com.mongodb.DBPortPool$SemaphoresOut: Out of semaphores to get db connection" error and by increasing the connections/multiplier I was able to solve that problem. I'm looking for links to or your best practices in configuring these options for production. The options for the 2.4 driver include: http://api.mongodb.org/java/2.4/com/mongodb/MongoOptions.html autoConnectRetry connectionsPerHost

I've a python script which works just as it should, but I need to write the execution time. I've googled that I should use timeit but I can't seem to get it to work. My Python script looks like this: import sys import getopt import timeit import random import os import re import ibm_db import time from string import maketrans myfile = open("results_update.txt", "a") for r in range(100): rannumber = random.randint(0, 100) update = "update TABLE set val = %i where MyCount >= '2010' and MyCount < '2012' and number = '250'" % rannumber #print rannumber conn = ibm_db.pconnect("dsn=myDB","usrname",

I am switching to PostgreSQL from SQLite for a typical Rails application. The problem is that running specs became slow with PG. On SQLite it took ~34 seconds, on PG it's ~76 seconds which is more than 2x slower . So now I want to apply some techniques to bring the performance of the specs on par with SQLite with no code modifications (ideally just by setting the connection options, which is probably not possible). Couple of obvious things from top of my head are: RAM Disk (good setup with RSpec on OSX would be good to see) Unlogged tables (can it be applied on the whole database so I don't