On 09/24/2012 03:53 PM, Dennis Brouwer wrote:
Last week I was repeatedly able to run all these tests on the database without any issue but recently, all of a sudden at random, some of the queries performed a factor 100 less. It may take hours to complete the transaction. At the same moment we see a dramatic decrease in IO and the CPU is nearly 100% busy in user space. After days of testing I may have found the cause: the ntp client. If I stop the ntp client the problem vanishes.
Any chance you are hitting this known linux bug in conjunction with a misconfigured ntp server? ie. does a
# date -s now fix the cpu load? http://blog.mozilla.org/it/2012/06/30/mysql-and-the-leap-second-high-cpu-and-the-fix/comment-page-1/#comment-1471 http://serverfault.com/questions/403732/anyone-else-experiencing-high-rates-of-linux-server-crashes-during-a-leap-second -- Marcello Perathoner webmaster@xxxxxxxxxxxxx -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
