Date: Wed, 12 Feb 2014 10:05:46 +0100 From: Egoitz Aurrekoetxea <egoitz@sarenet.es> To: freebsd-xen@freebsd.org Subject: About XenHVM network driver and mbuf tagging Message-ID: <68058FAE-C913-463E-A20C-67239C1220AE@sarenet.es>
next in thread | raw e-mail | index | archive | help
Hi all, If you=92re running FreeBSD 9.1 or greater (release versions tested = only) under Xen 4.1 in HVM mode (xen-detect is saying "Running in HVM = context on Xen v4.1.=94) AND if you use some (in combination of both, = and trying to see if with any other network drivers not involving = virtualization and using too the LRO piece of code of the FreeBSD = kernel) kind of software involving mbuf tagging too (Mac Framework, vlan = tagging, ipsec=85.) AND you move an important amount of traffic with = that driver (the net hvm driver in this case) you will see wired memory = starts increasing pretty fast and never being released. This seems to be = due to a problem with the LRO code of the FreeBSD kernel which causes = mbuf_tags not being properly released after the own mbuf chains have = been properly released. So as a temporary workaround (and really as = valid workaround without involving any kind of limitation) you can just = disable LRO flag in you interfaces running this driver (ifconfig = xn0-1-2=85. -lro) and you=92re done. This is a message for just trying to avoid people to waste time in = trying to find some workaround for the issue. For more info, I=92m = moving this topic at freebsd-hackers list with egoitz(at)ramattack.net = email address and with thread subject "mbuf_tag memory freeing issues = with LRO enabled on the XENHVM driver=94. Best regards, Egoitz Aurrekoetxea Departamento de sistemas 944 209 470 Parque Tecnol=F3gico. Edificio 103 48170 Zamudio (Bizkaia) egoitz@sarenet.es www.sarenet.es Antes de imprimir este correo electr=F3nico piense si es necesario = hacerlo.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?68058FAE-C913-463E-A20C-67239C1220AE>