To clarify I should ask I see that there is a zfs_arc_max parameter with `echo "::zfs_params" | mdb -k` but I am unsure which way to influence it best and whether it actually solves the issue since solaris 11.2 deprecated it as described here http://blog.zach.st/2014/08/02/control-the-size-of-the-zfs-arc-cache-dynamically.html
From: Matthias Götzke Sent: Monday, December 28, 2015 13:12 To: <[email protected]> Subject: ZFS ARC MAX ? Solaris 10 introduced the zfs_arc_max parameter. Is anything like this possible in SmartOS ? Background: We are having a number of issues with SmartOS Ram management and we hope this might lessen the impact a lot. Basically our servers run fine for a long time and then we add a small VM (e.g a smartos zone with 4GB ram) and suddenly the system basically comes to a halt. SSH is not possible anymore, HTTP Servers don’t react etc. This happens seemingly because the ARC grew to encompass the entire leftover RAM and when a new machine wants to use this RAM the kernel is reallocating pages. I have no idea why this would take so long as it does and why the entire system becomes unresponsive but this happens anyway. We can try forcing to free the RAM by running a little PERL script ahead of time allocating smaller. But this only means a lot of manual work, the same outages just in shorter bursts. It actually takes longer to free e.g 4GB of RAM from the ARC for a new machine than rebooting the entire server. Any tips ? Cheers, Matthias ------------------------------------------- smartos-discuss Archives: https://www.listbox.com/member/archive/184463/=now RSS Feed: https://www.listbox.com/member/archive/rss/184463/25769125-55cfbc00 Modify Your Subscription: https://www.listbox.com/member/?member_id=25769125&id_secret=25769125-7688e9fb Powered by Listbox: http://www.listbox.com
