We change very few settings in sysctl, and they're all the same changes from default on both hosts, but here's what everything's currently set to. Maybe some defaults have changed. I read through the diff, but nothing jumped out at me as plausibly relevant:
sysctl on a 3.2 kernel host with constant memory use: http://sprunge.us/ThQV sysctl on a 3.19 kernel host with excessively-growing memory use: http://sprunge.us/EIcB Diff of the two reports: http://sprunge.us/BfMY All of our deployments so far are on Linux, and nobody here has any experience with FreeBSD, so adding a new platform to support would be a pretty big investment, but it might be worth investigating if it would help get a kernel developer's attention. On Mon, Jan 4, 2016 at 7:49 PM, Krishna Kumar (Engineering) <[email protected]> wrote: > How about compare the sysctl settings from the two systems? > > On Tue, Jan 5, 2016 at 8:14 AM, Mark Felder <[email protected]> wrote: >> >> >> >> On Mon, Jan 4, 2016, at 20:24, Mark Felder wrote: >> > >> > >> > On Mon, Jan 4, 2016, at 19:16, Stephen Weeks wrote: >> > > We have several varnishd instances that have been running fine for >> > > years at constant memory use. We've recently decided to upgrade our >> > > linux distribution. After some troubleshooting, we were unable to >> > > find a configuration of Varnish on the new distro version that did not >> > > have dramatically higher memory usage. >> > >> > I suspect Linux kernel's memory management changes are your problem, not >> > Varnish. >> > >> > What is the version of the kernel on the instances that work well for >> > you? >> > >> > >> >> I don't have any expertise on kernels that new. My Linux knowledge ends >> around 2.6.32 :-) >> >> I'd probably look at Linux commits in git under mm/ which is where all >> the memory management code is at and read through until I saw something >> significant enough like some new knobs or a major overhaul that might be >> worth trying to back out and test with a custom kernel. >> >> If you have the time and the hardware I'd also try installing FreeBSD >> and testing your varnish config just to see another data point on memory >> usage. If it's considerably better, see if you can get a Linux kernel >> developer's attention and point out that 3.2 and a different OS both >> fare much, much better for your workload. They might have enough >> expertise to track down a regression. >> >> -- >> Mark Felder >> [email protected] >> >> _______________________________________________ >> varnish-misc mailing list >> [email protected] >> https://www.varnish-cache.org/lists/mailman/listinfo/varnish-misc > > _______________________________________________ varnish-misc mailing list [email protected] https://www.varnish-cache.org/lists/mailman/listinfo/varnish-misc
