Are all 8 vcpus actually online and in use in the Linux image? Lee Stewart ● VM System Support ● Visa ● Phone: 6(750)4601 - +1-303-389-4601 ● lstew...@visa.com
-----Original Message----- From: Linux on 390 Port [mailto:LINUX-390@VM.MARIST.EDU] On Behalf Of Martha McConaghy Sent: Tuesday, September 19, 2017 12:25 PM To: LINUX-390@VM.MARIST.EDU Subject: Tuning setting in Ubuntu? I have a project that is experiencing something interesting. They are doing continuous integration builds on zLinux servers using various versions of Linux, i.e. SLES, RHEL and Ubuntu. All are running on the same z/VM system (6.3) and there seems to be plenty of available CPU and memory overall. The jobs running on the RHEL and SLES systems run in a reasonable amount of time, but the ones on the Ubuntu system run more than twice as long. Some have even timed out because they didn't finish in the expected CI window. Meanwhile, the LPAR and z/VM system are not even breaking a sweat. All of them have the same resources, i.e. 8 vcpus, and 16G of memory. The project folks report seeing a lot of cpu "steals" on the Ubuntu system. I'm thinking of giving them more vcpus to help out with that. However, I also wonder if there is a tuning variable or kernel setting that is different by default on Ubuntu than on the SLES or RHEL distributions? The problem seemed to start back in August, though they have been running these jobs for over a year. Perhaps a patch got pushed out that changed some settings? (I've seen Ubuntu service do weird things to other servers.) I don't much about Ubuntu except that I dislike it intensely. Does anyone have any suggestions as to what to look at? Martha ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/ ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
