uploaded to x/b/e/f/g, thanks! -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to libseccomp in Ubuntu. https://bugs.launchpad.net/bugs/1861177
Title: seccomp_rule_add is very slow Status in snapd: Invalid Status in libseccomp package in Ubuntu: In Progress Status in libseccomp source package in Xenial: In Progress Status in libseccomp source package in Bionic: In Progress Status in libseccomp source package in Eoan: In Progress Status in libseccomp source package in Focal: In Progress Status in libseccomp source package in Groovy: In Progress Bug description: [IMPACT] There is a known and patched issue with version 2.4 of libseccomp where certain operations have a large performance regression. This is causing some packages that use libseccomp such as container orchestration systems to occasionally time out or otherwise fail under certain workloads. Please consider porting the patch into the various Ubuntu versions that have version 2.4 of libseccomp and into the backports. The performance patch from version 2.5 (yet to be released) applies cleanly on top of the 2.4 branch of libseccomp. For more information, and for a copy of the patch (which can also be cherry picked from the upstream libseccomp repos) see the similar Debian issue: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=943913 Upstream issue : https://github.com/seccomp/libseccomp/issues/153 Upstream fix : https://github.com/seccomp/libseccomp/pull/180/ [Test Case] For this test case we use Docker on Ubuntu Groovy (20.10) : --> Current libseccomp version #dpkg -l | grep libseccomp ii libseccomp2:amd64 2.4.3-1ubuntu3 amd64 high level interface to Linux seccomp filter ## pull ubuntu image # docker pull ubuntu ## create a container # docker run --name test_seccomp -it 74435f89ab78 /bin/bash ## run test case # for i in `seq 1 40`; do (time sudo docker exec test_seccomp true &); done ... MAX TIME : real 0m10,319s user 0m0,018s sys 0m0,033s --> Patched libseccomp version # dpkg -l | grep libseccomp ii libseccomp2:amd64 2.4.3-1ubuntu4 amd64 high level interface to Linux seccomp filter # docker start test_seccomp ## run test case # for i in `seq 1 40`; do (time sudo docker exec test_seccomp true &); done ... MAX TIME : real 0m3,650s user 0m0,025s sys 0m0,028s [Regression Potential] The first of the 2 patches cleans up the code that adds rules to a single filter without changing the logic of the code. The second patch introduces the idea of shadow transactions. On a successful transaction commit the old transaction checkpoint is preserved and is brought up to date with the current filter. The next time a new transaction starts, it checks is the a shadow transaction exist and if so the shadow is used instead of creating a new checkpoint from scratch [1]. This is the patch that mitigates the performance regression. Any potential regression will involve the parts of the code that add rules to filters and/or the code that creates and checks the shadow transactions. [Other] Affected releases : Groovy, Focal, Eoan, Bionic, Xenial. [1] https://github.com/seccomp/libseccomp/pull/180/commits/bc3a6c0453b0350ee43e4925482f705a2fbf5a4d To manage notifications about this bug go to: https://bugs.launchpad.net/snapd/+bug/1861177/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
