Hetzner mail to customers: 1 megawatt more power due to leap second
(Was Google translate, now from the comment of imaginator below, thanks)
Better translation of their message to English speaking customers:
During the night of 30.06.2012 to 01.07.2012 our internal monitoring systems registered an increase in the level of IT power usage by approximately one megawatt.
The reason for this huge surge is the additional switched leap second which can lead to permanent CPU load on Linux servers.
According to heise.de, various Linux distributions are affected by this. Further information can be found at: http://www.h-online.com/open/news/item/Leap-second-Linux-can...
In order to reduce CPU load to a normal level again, a restart of the whole system is necessary in many cases. First, a soft reboot via the command line should be attempted. Failing that, you have the option of performing a hardware reset via the Robot administration interface. For this, select menu item "Server" and the "Reset" tab for the respective server in the administration interface. Please do not hesitate to contact us, should you have any queries.
Kind regards,
Hetzner Online AG Stuttgarter Str. 1 91710 Gunzenhausen / Germany info@hetzner.de http://www.hetzner.com
In this technical retrospective (2012), @Uchikoma shares practical architectural lessons learned from running, scaling, or migrating production software under lean constraints.
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Better translation of their message to English speaking customers:
During the night of 30.06.2012 to 01.07.2012 our internal monitoring systems registered an increase in the level of IT power usage by approximately one megawatt.
The reason for this huge surge is the additional switched leap second which can lead to permanent CPU load on Linux servers.
According to heise.de, various Linux distributions are affected by this. Further information can be found at: http://www.h-online.com/open/news/item/Leap-second-Linux-can-freeze-1629805.html
In order to reduce CPU load to a normal level again, a restart of the whole system is necessary in many cases. First, a soft reboot via the command line should be attempted. Failing that, you have the option of performing a hardware reset via the Robot administration interface. For this, select menu item "Server" and the "Reset" tab for the respective server in the administration interface.
Please do not hesitate to contact us, should you have any queries.
Kind regards,
Hetzner Online AG Stuttgarter Str. 1 91710 Gunzenhausen / Germany info@hetzner.de http://www.hetzner.com
No need for Google translate:
During the night of 30.06.2012 to 01.07.2012 our internal monitoring systems registered an increase in the level of IT power usage by approximately one megawatt.
The reason for this huge surge is the additional switched leap second which can lead to permanent CPU load on Linux servers.
According to heise.de, various Linux distributions are affected by this. Further information can be found at: http://www.h-online.com/open/news/item/Leap-second-Linux-can-freeze-1629805.html
Please do not hesitate to contact us, should you have any queries.
OVH https://twitter.com/olesovhcom/status/220142781895671810
Nice graph from Hetzner showing the spike:
http://imgur.com/a/ykoup
Perhaps nitpicking, but this is because of a bug in the leap second implementation, not in the leap second per se.