On 25/04/2019 17:50, Ian Jackson wrote: > Most hardware that supports i386 supports amd64 too. When doing > builds we do need the right userland, but we don't actually care what > the kernel is doing. With Linux 32-on-64 is good for that. > > Especially, there is a kernel regression (evident in the Debian > stretch kernel, but not present in jessie's) where 32-bit Linux > mismanages the memory on hosts with moderately large amounts of > RAM (ie, significantly more RAM than can be addressed at once), > resulting in what amounts to a near-stall of the paging system. Since > the paging system is used for filesystem writes too, the effect is > that commands run by builds can take totally unreasonable amounts of > time. Ie, this version of Linux is broken when i386 PAE is needed. > > In practice this is causing significant trouble in the Xen Project CI. > > This kernel bug probably won't affect our test jobs because > (i) we use our own kernels, so we would probably detect this > regression when switching kernel branches etc. (ii) test jobs > run with a dom0_mem setting which avoids the preconditions for the > particular bug. > > CC: Juergen Gross <jgr...@suse.com> > CC: Boris Ostrovsky <boris.ostrov...@oracle.com> > CC: Wei Liu <wei.l...@citrix.com> > CC: Andrew Cooper <andrew.coop...@citrix.com> > CC: Paul Durrant <paul.durr...@citrix.com> > Signed-off-by: Ian Jackson <ian.jack...@eu.citrix.com>
Acked-by: Juergen Gross <jgr...@suse.com> Juergen _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
