recently we revoked grants of localhost on mysql .
I had mysql and scripts running on same server and we use to connect data mysql through socket (localhost) and it used to take 1 hr for a data intensive script to run.
But when we starting using TCP/IP to connect to mysql my script's execution time increased drastically. now it takes 3.5 hr to complete.
Can somebody suggest what could be the possible reason?
I understand moving from local socket connection to TCP/IP would increase time but the leap would be this much I'm unable to figure out.
Please help me
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Is there a way to keep a mysql server stopped and for it to be started only after a connection is attempted.
I have a development mysql server in my ubuntu machine and I would like to keep it stopped unless needed and I don't want to have to remember to start it manually.
It's ok if this can be solved using something like vagrant or docker.
Bonus point if the server can be shut down after a configurable amount of idle time.
I remember openshift did something like this, if not connections were made the vm would be shut down and be started only after some connection was attempted to it.
Any MySQL client will attempt to connect to port 3306 (by default) to establish a MySQL connection. If the MySQL server is not running, there's nothing listening on port 3306, so the connection will simply fail.
To do what you're describing, there would need to be something listening on port 3306. Perhaps a proxy of some kind, like HAProxy or ProxySQL. Perhaps one of these can be configured to start a service on demand, but I've never seen anyone attempt to do that.
The reason is that it takes some time to start up a MySQL server process. At least a few seconds, but it could be much longer, depending on whether the server needs to perform crash recovery if it wasn't shut down cleanly last time it stopped. The proxy that starts it would have to keep re-trying the connection until it responds.
There's also a possibility that a downed MySQL server cannot be started, for example if there's a configuration problem that prevents it from starting, or a corrupted database. Then your client would try repeatedly to connect, with a delay each time, and never be able to start the service.
I wonder if what you really need is not MySQL, but an embedded database like SQLite.
My Windows 2003 server installed updates this morning and since then MYSQL starts but doesn't listen on port 3306. I have searched for a solution but so far nothing has helped.
I get the error: Can't connect to MySQL server on 'localhost' (10061)
I have my firewall switched off. I can see the mysqld process running, I've checked the MYSQL error log and event viewer. I've used netstat and can see that MYSQL is not listening on port 3306.
From various posts about the issues I have tried:
Trying to connect by IP eg. 127.0.0.1
Backing up my my.ini file and re-configuring using the MYSQL config wizard. I have since restored the original file.
Backing up then removing the ibdata1, ib_logfile0, ib_logfile1 files. I have since restored the original files.
Ensuring there is a firewall rule even though my firewall is off.
Working through my ini file to make sure that port 3306 is enabled and enabling TCP/IP connections (I've always used localhost in the past without a problem).
Running mysqladmin to make sure that port 3306 is specified.
Rebooting several times.
Starting my web, MYSQL and other services in various orders in case one service or another was trying to reserve the port for itself.
I'm getting no errors in the MYSQL error log and just a warning in Event Viewer: Changed limits: max_open_files: 2048 max_connections: 1024 table_cache: 507 - which I think is fine.
Thank you for those who took the time to comment.
Miraculously the MYSQL service has now started and is running fine at least until the next re-boot.
I have no idea why it wasn't working or what changed in the environment to make it work as I changed nothing since my original question nor did I restart the service. I suspect another service stalling / interfering with it. If I do get to the bottom of it though I will post it here.
I've setup a MySQL server on Ubuntu machine.
When running a heavy query (the table has over 1M rows), the database becomes unresponsive.
Upon connection it returns:
Can't connect to MySQL server on 'ip address' (110)
To make it responsive again, I need to kill the process of the heavy query (visible under "show processlist").
Is there a way of preventing this? I used to host the same database on Rackspace MySQL server. Even though it had the same amount of memory, it was more efficient and it never became unresponsive even when running similar queries.
I've had a Rails application running in production for the past 6 months, with weekly deployments, without any issue.
Now, I've been having a recurring issue for about 3 weeks and it seems to get worst every week.
When my app boots and reaches the point where it's trying to connect to the DB, I get this error :
Can't connect to MySQL server on '***.amazonaws.com' (110) (Mysql2::Error)
AFAIK, this error tells me that I've reached MySQL's max connections limit.
From the configs, I should be able to open 296 connections. My app is set to run 7 instances with each a database connection pool of 5, so it can't really exceed 70 connections when deploying a new instance.
I've never seen the connection count go above 20 in either the AWS RDS Console or the SHOW PROCESSLIST command.
I don't think it has anything to do with either Rails or my application server (Puma), since I can't connect through the MySQL Command-Line Tool when the issue occurs.
Has anyone had a similar issue with MySQL on RDS or MySQL itself?
The database pool isn't per application, it's per process. If it's threading/multi process per instance it could be using more than that. Have you tried restarting mysql? It sounds like you have some hanging connections for whatever reason.
I've been getting these issues recently. Could it be related to the pending-restart change of parameter group on my RDS Instance? I sure hope not. As I understand a pending change should have no effect on the current performance.
I use XAMPP 1.7.3
If I try to open phpMyAdmin it will try to open but eventually I'll have only a blank page, no errors.
If I try to connect with Navicat, the same thing, it will not be able to establish a connection.
And usually this process takes between 30% and 60% of the processor for more than 20 min.
If I stop and then start again the mysql server from XAMPP Control Panel the message is 'Mysql server started'.
But If I go to http://localhost/xampp/ and then 'Status' everything is 'Activated' EXCEPT ' MySQL database', 'SMTP Service', 'FTP Service' which are 'Deactivated'.
I think I crashed the Mysql server after I tried to make a database backup BUT the laptop closed before the backup was finished (the battery was discharged).
How can I repair the connection to the Mysql server?
First, make sure to double check the obvious, most likely these are not the issues since it happened after you closed your laptop, but it doesn't hurt to double check:
Make sure the MySQL service is running...
Also make sure that a firewall is not blocking port 3306...
This guide covers both MyISAM and InnoDB: http://www.softwareprojects.com/resources/programming/t-how-to-fix-mysql-database-myisam-innodb-1634.html
Now, assuming that the tables are MyISAM, you can repair them by following this guide:
http://colekcolek.com/2011/11/02/repair-corrupted-mysql-myisam-table/
Here is a way to do it for InnoDB: http://code.google.com/p/innodb-tools/