I built a test kernel with the patch referenced in the description. The test kernel can be downloaded from: http://kernel.ubuntu.com/~jsalisbury/lp1752236
Can you test this kernel and see if it resolves this bug? Note, to test this kernel, you need to install both the linux-image and linux-image-extra .deb packages. Thanks in advance! -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1752236 Title: Ubuntu 18.04 - Performance: Radix page fault handler bug in KVM Status in The Ubuntu-power-systems project: In Progress Status in linux package in Ubuntu: In Progress Status in linux source package in Bionic: In Progress Bug description: == Comment: #0 - JENIFER HOPPER <jhop...@us.ibm.com> - 2018-02-27 17:25:59 == +++ This bug was initially created as a clone of Bug #165215 +++ ---Problem Description--- Paul Mackerras has posted a fix to a Radix page fault handler bug in KVM: http://patchwork.ozlabs.org/patch/877033/ " KVM: PPC: Book3S HV: Fix handling of large pages in radix page fault handler " This is critical for P9 KVM performance. Using an open source database workload, we saw an 11% throughput improvement with this patch when the guest was backed w/ 2MB hugepages. Without this patch, hugepage backing does not help performance compared to base page size. ---uname output--- 18.04 lts Machine Type = 5104-22C ---Debugger--- A debugger is not configured ---Steps to Reproduce--- Back guest w/ 2MB pages, run a throughput test and compare performance. Contact Information = jhop...@us.ibm.com To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1752236/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
