This bug is awaiting verification that the linux-azure/5.15.0-1006.7 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy' to 'verification-done-jammy'. If the problem still exists, change the tag 'verification-needed-jammy' to 'verification-failed-jammy'.
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you! ** Tags added: verification-needed-jammy -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-azure in Ubuntu. https://bugs.launchpad.net/bugs/1971701 Title: Azure: swiotlb patch needed for CVM Status in linux-azure package in Ubuntu: Invalid Status in linux-azure source package in Jammy: Fix Committed Bug description: SRU Justification [Impact] [Azure][CVM] Include the swiotlb patch to increase the disk/network performance Description As we discussed, there will be new CVM-supporting linux-azure kernels that're based on v5.13 and v5.15. Here I'm requesting the below patch to be included into the two kernels because it can significantly improve the disk/network performance: swiotlb: Split up single swiotlb lock: https://github.com/intel/tdx/commit/4529b5784c141782c72ec9bd9a92df2b68cb7d45 We have tested the patch with the upstream 5.16-rc8. BTW, the patch is unlikely to be in the mainline kernel, as the community is trying to resolve the lock contention issue in the swiotlb code using a different per-device per-queue implementation, which would need quite some time to be finalized -- before that happens, we need this out-of-tree patch to achieve good disk/network performance for CVM GA on Azure. (BTW, the v5.4-based linux-azure-cvm kernel does not need the patch, because it uses a private bounce buffer implementation: drivers/hv/hv_bounce.c, which doesn’t have the I/O performance issue caused by lock contention in the mainline kernel’s swiotlb code.) [Test Case] [Microsoft tested] I tried the April-27 amd64 test kernel and it worked great for me: 1. The test kernels booted up successfully with 256 virtual CPUs + 100 GB memory. 2. The kernel worked when I changed the MTU of the NetVSC NIC. 3. The Hyper-V HeartBeat/TimeSync/ShutDown VMBsus devices also worked as expected. 4. I did some quick disk I/O and network stress tests and found no issue. When I did the above tests, I changed the low MMIO size to 3GB (which is the setting for a VM on Azure today) by "set-vm decui-u2004-cvm -LowMemoryMappedIoSpace 3GB". Our test team will do more testing, including performance test. We expect the performance of this v5.15 test kernel should be on par with the v5.4 linux-azure-cvm kernel. [Where things could go wrong] Networking could fail or continue to suffer from poor performance. [Other Info] SF: #00332721 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-azure/+bug/1971701/+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
