Easier, but the pages aren't dropped from the zVM side immediately so if you are memory constrained there, cmmflush is your friend.
-----Original Message----- From: Linux on 390 Port [mailto:LINUX-390@VM.MARIST.EDU] On Behalf Of Michael MacIsaac Sent: Thursday, July 09, 2015 8:51 AM To: LINUX-390@VM.MARIST.EDU Subject: Re: [LINUX-390] How to find a memory leak? Tomas, > I forgot to answer this question: you can drop buffers and cache by running > echo 3 > /proc/sys/vm/drop_caches Nice, even easier. Thanks! The next question is - can this ever be done by a non-root user? I tried adding /bin/echo to /etc/sudoers, but still get an error: mike@lab153:~ $ sudo /bin/echo 3 > /proc/sys/vm/drop_caches -bash: /proc/sys/vm/drop_caches: Permission denied -Mike On Thu, Jul 9, 2015 at 11:36 AM, Pavelka, Tomas <tomas.pave...@ca.com> wrote: > > Thanks. I copied and pasted cmmflush and it seems to work nicely > > If I understand it right then you have to look at how cmmflush affects > the output of /proc/buddyinfo. If you see non-zero in the last order > of slab (i.e. the one with 1MB size) then you are good to run vmcp > --buffer=1M. > Otherwise you may still run into problems even if free -m shows a lot > of free memory. > > But I have not tried cmmflush, maybe it will help. > > The way that I was able to reproduce the memory fragmentation problem > was by copying large amount of data over SCP to that Linux machine. > Try that and see if you can reproduce the vmcp --buffer=1M failure. > > Tomas > ---------------------------------------------------------------------- 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/
