I migrated a web site from one host to another and as such upgraded to MySQL 5.5 running on Ubuntu 12.04. Everything was moving along nicely until MySQL started to randomly crash.
Jul 23 07:06:38 domU-12-31-39-02-76-EA kernel: [236645.626405] init: mysql main process (21515) terminated with status 1
Jul 23 07:06:38 domU-12-31-39-02-76-EA kernel: [236645.626453] init: mysql main process ended, respawning
Jul 23 07:06:39 domU-12-31-39-02-76-EA kernel: [236646.617559] init: mysql post-start process (21516) terminated with status 1
Trying to start the process using the service command yields this message:
Job failed to start
I found several sites recommending that I uninstall and re-install mysqld – which I did to no avail.
I finally tried to run mysqld manually from command line and found a bit more of a clue:
I was completely frustrated with the speed of my network connection so I decided to do some investigation. I was convinced that Comcast was to blame and even placed a call to their support department to complain. They told me that the network speeds were as promised and everything checked out. They reset the connection and told me there was nothing they could do.
I ran speed tests (over at http://speedtest.net) and found the download speeds to be anywhere from .66Mbps to .99Mbps.
I tried disabling the security to no avail. I tried disabling the firewall and Upnp – again speeds hovered around 1Mbps. Finally, I disabled WMM support and POW! Speeds increased to over 35Mbps. Below is the screenshot of Cisco configuration.
To modify the configuration, login to your router and select Applications & Gaming, then click QoS and click Disable next to the WMM Support option. WMM or Wireless Multi-Media Extensions were created to enable better performance (Quality of Service) for video and voice traffic but have the unintended effect of destroying wireless performance. (more…)