[Kernel-packages] [Bug 1344323] Re: Trusty kernel network performance regression
This bug was fixed in the package linux - 3.13.0-35.62 --- linux (3.13.0-35.62) trusty; urgency=low [ Joseph Salisbury ] * Release Tracking Bug - LP: #1357148 [ Brad Figg ] * Start new release [ dann frazier ] * SAUCE: (no-up) Fix build failure on arm64 - LP: #1353657 * [debian] Allow for package revisions condusive for branching [ David Henningsson ] * SAUCE: Call broadwell specific functions from the hda driver - LP: #1317865 [ Edward Lin ] * SAUCE: (no-up) Add use native backlight quirk for Dell Inspiron 5547/5447 - LP: #1332437 [ Imre Deak ] * SAUCE: drm/i915: move power domain init earlier during system resume - LP: #1353405 [ Jani Nikula ] * SAUCE: drm/i915: use lane count and link rate from VBT as minimums for eDP - LP: #1338582 * SAUCE: drm/i915/dp: force eDP lane count to max available lanes on BDW - LP: #1338582 * SAUCE: drm/i915: provide interface for audio driver to query cdclk - LP: #1188091 * SAUCE: drm/i915: demote opregion excessive timeout WARN_ONCE to DRM_INFO_ONCE - LP: #1351014 [ Joseph Salisbury ] * [Config] updateconfigs after Linux 3.13.11.6 updates [ Luis Henriques ] * Revert [Packaging] linux-udeb-flavour -- standardise on linux prefix [ Ming Lei ] * Revert SAUCE: (no-up) ata: Fix the dma state machine lockup for the IDENTIFY DEVICE PIO mode command. - LP: #1335645 [ Paulo Zanoni ] * SAUCE: drm/i915: consider the source max DP lane count too - LP: #1338582 [ Tim Gardner ] * [Config] CONFIG_GPIO_SYSFS=y - LP: #1342153 * [Config] CONFIG_KEYS_DEBUG_PROC_KEYS=y - LP: #1344405 * [Config] updateconfigs * [Config] CONFIG_SCSI_IPR_TRACE=y, CONFIG_SCSI_IPR_DUMP=y - LP: #1343109 * [Config] CONFIG_CONTEXT_TRACKING_FORCE=n - LP: #1349028 [ Timo Aaltonen ] * SAUCE: Fix a typo in hda i915_bdw support. - LP: #1343140 [ Upstream Kernel Changes ] * Revert net/mlx4_en: Fix bad use of dev_id - LP: #1347012 * Revert ACPI / AC: Remove AC's proc directory. - LP: #1356913 * Revert mac80211: move bufferable MMPDU check to fix AP mode scan - LP: #1356913 * mm, pcp: allow restoring percpu_pagelist_fraction default - LP: #1347088 * net: Fix permission check in netlink_connect() - LP: #1312989 * netlink: Rename netlink_capable netlink_allowed - LP: #1312989 * net: Move the permission check in sock_diag_put_filterinfo to packet_diag_dump - LP: #1312989 * net: Add variants of capable for use on on sockets - LP: #1312989 * net: Add variants of capable for use on netlink messages - LP: #1312989 * net: Use netlink_ns_capable to verify the permisions of netlink messages - LP: #1312989 * netlink: Only check file credentials for implicit destinations - LP: #1312989 * igb: fix stats for i210 rx_fifo_errors - LP: #1338893 * HID: use multi input quirk for 22b9:2968 - LP: #1339567 * crypto/nx: disable NX on little endian builds - LP: #1338666 * ACPI / video: Add Dell Inspiron 5737 to the blacklist - LP: #1250401 * Input: elantech - deal with clickpads reporting right button events - LP: #1188025 * net/mlx4_core: Enforce irq affinity changes immediatly - LP: #1326108 * cpumask: Utility function to set n'th cpu - local cpu first - LP: #1326108 * net/mlx4_en: Use affinity hint - LP: #1326108 * net/mlx4_en: Don't use irq_affinity_notifier to track changes in IRQ affinity map - LP: #1326108 * net/mlx4_en: IRQ affinity hint is not cleared on port down - LP: #1326108 * Subject: net: Allow tc changes in user namespaces - LP: #1344049 * net-gro: restore frag0 optimization - LP: #1344323 * Bluetooth: Fix redundant encryption request for reauthentication - LP: #1347088 * Bluetooth: Fix check for connection encryption - LP: #1347088 * introduce for_each_thread() to replace the buggy while_each_thread() - LP: #1347088 * NFS: Don't declare inode uptodate unless all attributes were checked - LP: #1347088 * usb: dwc3: gadget: clear stall when disabling endpoint - LP: #1347088 * ACPICA: utstring: Check array index bound before use. - LP: #1347088 * mtip32xx: Increase timeout for STANDBY IMMEDIATE command - LP: #1347088 * mtip32xx: Remove dfs_parent after pci unregister - LP: #1347088 * mtip32xx: Fix ERO and NoSnoop values in PCIe upstream on AMD systems - LP: #1347088 * extcon: max77693: Fix two NULL pointer exceptions on missing pdata - LP: #1347088 * extcon: max8997: Fix NULL pointer exception on missing pdata - LP: #1347088 * builddeb: use $OBJCOPY variable instead of objcopy - LP: #1347088 * bluetooth: hci_ldisc: fix deadlock condition - LP: #1347088 * powerpc/pseries: Fix overwritten PE state - LP: #1347088 * PCI: Add new ID for Intel GPU spurious interrupt quirk - LP: #1347088 * x86-32, espfix: Remove
[Kernel-packages] [Bug 1344323] Re: Trusty kernel network performance regression
** Changed in: linux (Ubuntu Trusty) Status: In Progress = Fix Committed -- 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/1344323 Title: Trusty kernel network performance regression Status in “linux” package in Ubuntu: Fix Released Status in “linux” source package in Trusty: Fix Committed Bug description: SRU Justification: Impact: Reduced TCP/IP receive performance for network devices that do not split packet headers into skb linear area (e.g., mlx4). The trusty kernel has incorporated commit eff44f9cc9a02aad53d568d3ae5020b6792ae4f6 Author: Jerry Chu hk...@google.com Date: Wed Dec 11 20:53:45 2013 -0800 net-gro: Prepare GRO stack for the upcoming tunneling support which modifies the GRO frag0 optimization, but unfortunately for some cases results in calls to __skb_pull_tail for every packet being received via the GRO path. This causes a reduction in TCP receive performance (or, more accurately, an increase in CPU load for TCP receive processing, which will cause throughput reduction for CPU limited workloads). Fix: This has already been fixed in mainline in commit a50e233c50dbc881abaa0e4070789064e8d12d70 Author: Eric Dumazet eduma...@google.com Date: Sat Mar 29 21:28:21 2014 -0700 net-gro: restore frag0 optimization The fix has been backported to and verified on the trusty kernel using mlx4 devices and iperf; an increase from 7.5 to 8.5 Gb/sec was observed when adding the patch, and the relevant portion of perf captures show changes in the call paths from: 7.17%iperf [kernel.kallsyms] [k] __pskb_pull_tail | --- __pskb_pull_tail | |--48.03%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--28.53%-- napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--13.11%-- inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq to: 4.87% iperf [kernel.kallsyms] [k] skb_gro_receive | --- skb_gro_receive | |--98.13%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq Testcase: The fix was tested using mlx4 10Gb/sec network devices between two arm64 systems using iperf -s on one end and iperf -c on the other. The unmodified kernel reported approximately 7.5 Gb/sec throughput, the fixed kernel approximately 8.5 Gb/sec. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1344323/+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
[Kernel-packages] [Bug 1344323] Re: Trusty kernel network performance regression
I'm seeing the expected performance with the SRU kernel (technically a different build with a couple of SATA patches required to boot) ** Tags removed: verification-needed-trusty ** Tags added: verification-done-trusty -- 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/1344323 Title: Trusty kernel network performance regression Status in “linux” package in Ubuntu: Fix Released Status in “linux” source package in Trusty: Fix Committed Bug description: SRU Justification: Impact: Reduced TCP/IP receive performance for network devices that do not split packet headers into skb linear area (e.g., mlx4). The trusty kernel has incorporated commit eff44f9cc9a02aad53d568d3ae5020b6792ae4f6 Author: Jerry Chu hk...@google.com Date: Wed Dec 11 20:53:45 2013 -0800 net-gro: Prepare GRO stack for the upcoming tunneling support which modifies the GRO frag0 optimization, but unfortunately for some cases results in calls to __skb_pull_tail for every packet being received via the GRO path. This causes a reduction in TCP receive performance (or, more accurately, an increase in CPU load for TCP receive processing, which will cause throughput reduction for CPU limited workloads). Fix: This has already been fixed in mainline in commit a50e233c50dbc881abaa0e4070789064e8d12d70 Author: Eric Dumazet eduma...@google.com Date: Sat Mar 29 21:28:21 2014 -0700 net-gro: restore frag0 optimization The fix has been backported to and verified on the trusty kernel using mlx4 devices and iperf; an increase from 7.5 to 8.5 Gb/sec was observed when adding the patch, and the relevant portion of perf captures show changes in the call paths from: 7.17%iperf [kernel.kallsyms] [k] __pskb_pull_tail | --- __pskb_pull_tail | |--48.03%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--28.53%-- napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--13.11%-- inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq to: 4.87% iperf [kernel.kallsyms] [k] skb_gro_receive | --- skb_gro_receive | |--98.13%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq Testcase: The fix was tested using mlx4 10Gb/sec network devices between two arm64 systems using iperf -s on one end and iperf -c on the other. The unmodified kernel reported approximately 7.5 Gb/sec throughput, the fixed kernel approximately 8.5 Gb/sec. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1344323/+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
[Kernel-packages] [Bug 1344323] Re: Trusty kernel network performance regression
** Branch linked: lp:ubuntu/precise-proposed/linux-lts-trusty -- 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/1344323 Title: Trusty kernel network performance regression Status in “linux” package in Ubuntu: Fix Released Status in “linux” source package in Trusty: In Progress Bug description: SRU Justification: Impact: Reduced TCP/IP receive performance for network devices that do not split packet headers into skb linear area (e.g., mlx4). The trusty kernel has incorporated commit eff44f9cc9a02aad53d568d3ae5020b6792ae4f6 Author: Jerry Chu hk...@google.com Date: Wed Dec 11 20:53:45 2013 -0800 net-gro: Prepare GRO stack for the upcoming tunneling support which modifies the GRO frag0 optimization, but unfortunately for some cases results in calls to __skb_pull_tail for every packet being received via the GRO path. This causes a reduction in TCP receive performance (or, more accurately, an increase in CPU load for TCP receive processing, which will cause throughput reduction for CPU limited workloads). Fix: This has already been fixed in mainline in commit a50e233c50dbc881abaa0e4070789064e8d12d70 Author: Eric Dumazet eduma...@google.com Date: Sat Mar 29 21:28:21 2014 -0700 net-gro: restore frag0 optimization The fix has been backported to and verified on the trusty kernel using mlx4 devices and iperf; an increase from 7.5 to 8.5 Gb/sec was observed when adding the patch, and the relevant portion of perf captures show changes in the call paths from: 7.17%iperf [kernel.kallsyms] [k] __pskb_pull_tail | --- __pskb_pull_tail | |--48.03%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--28.53%-- napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--13.11%-- inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq to: 4.87% iperf [kernel.kallsyms] [k] skb_gro_receive | --- skb_gro_receive | |--98.13%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq Testcase: The fix was tested using mlx4 10Gb/sec network devices between two arm64 systems using iperf -s on one end and iperf -c on the other. The unmodified kernel reported approximately 7.5 Gb/sec throughput, the fixed kernel approximately 8.5 Gb/sec. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1344323/+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
[Kernel-packages] [Bug 1344323] Re: Trusty kernel network performance regression
This bug is awaiting verification that the 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- trusty' to 'verification-done-trusty'. 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-trusty -- 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/1344323 Title: Trusty kernel network performance regression Status in “linux” package in Ubuntu: Fix Released Status in “linux” source package in Trusty: In Progress Bug description: SRU Justification: Impact: Reduced TCP/IP receive performance for network devices that do not split packet headers into skb linear area (e.g., mlx4). The trusty kernel has incorporated commit eff44f9cc9a02aad53d568d3ae5020b6792ae4f6 Author: Jerry Chu hk...@google.com Date: Wed Dec 11 20:53:45 2013 -0800 net-gro: Prepare GRO stack for the upcoming tunneling support which modifies the GRO frag0 optimization, but unfortunately for some cases results in calls to __skb_pull_tail for every packet being received via the GRO path. This causes a reduction in TCP receive performance (or, more accurately, an increase in CPU load for TCP receive processing, which will cause throughput reduction for CPU limited workloads). Fix: This has already been fixed in mainline in commit a50e233c50dbc881abaa0e4070789064e8d12d70 Author: Eric Dumazet eduma...@google.com Date: Sat Mar 29 21:28:21 2014 -0700 net-gro: restore frag0 optimization The fix has been backported to and verified on the trusty kernel using mlx4 devices and iperf; an increase from 7.5 to 8.5 Gb/sec was observed when adding the patch, and the relevant portion of perf captures show changes in the call paths from: 7.17%iperf [kernel.kallsyms] [k] __pskb_pull_tail | --- __pskb_pull_tail | |--48.03%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--28.53%-- napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--13.11%-- inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq to: 4.87% iperf [kernel.kallsyms] [k] skb_gro_receive | --- skb_gro_receive | |--98.13%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq Testcase: The fix was tested using mlx4 10Gb/sec network devices between two arm64 systems using iperf -s on one end and iperf -c on the other. The unmodified kernel reported approximately 7.5 Gb/sec throughput, the fixed kernel approximately 8.5 Gb/sec. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1344323/+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
[Kernel-packages] [Bug 1344323] Re: Trusty kernel network performance regression
** Branch linked: lp:ubuntu/trusty-proposed/linux-keystone -- 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/1344323 Title: Trusty kernel network performance regression Status in “linux” package in Ubuntu: Fix Released Status in “linux” source package in Trusty: In Progress Bug description: SRU Justification: Impact: Reduced TCP/IP receive performance for network devices that do not split packet headers into skb linear area (e.g., mlx4). The trusty kernel has incorporated commit eff44f9cc9a02aad53d568d3ae5020b6792ae4f6 Author: Jerry Chu hk...@google.com Date: Wed Dec 11 20:53:45 2013 -0800 net-gro: Prepare GRO stack for the upcoming tunneling support which modifies the GRO frag0 optimization, but unfortunately for some cases results in calls to __skb_pull_tail for every packet being received via the GRO path. This causes a reduction in TCP receive performance (or, more accurately, an increase in CPU load for TCP receive processing, which will cause throughput reduction for CPU limited workloads). Fix: This has already been fixed in mainline in commit a50e233c50dbc881abaa0e4070789064e8d12d70 Author: Eric Dumazet eduma...@google.com Date: Sat Mar 29 21:28:21 2014 -0700 net-gro: restore frag0 optimization The fix has been backported to and verified on the trusty kernel using mlx4 devices and iperf; an increase from 7.5 to 8.5 Gb/sec was observed when adding the patch, and the relevant portion of perf captures show changes in the call paths from: 7.17%iperf [kernel.kallsyms] [k] __pskb_pull_tail | --- __pskb_pull_tail | |--48.03%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--28.53%-- napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--13.11%-- inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq to: 4.87% iperf [kernel.kallsyms] [k] skb_gro_receive | --- skb_gro_receive | |--98.13%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq Testcase: The fix was tested using mlx4 10Gb/sec network devices between two arm64 systems using iperf -s on one end and iperf -c on the other. The unmodified kernel reported approximately 7.5 Gb/sec throughput, the fixed kernel approximately 8.5 Gb/sec. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1344323/+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
[Kernel-packages] [Bug 1344323] Re: Trusty kernel network performance regression
** Changed in: linux (Ubuntu Trusty) Importance: Undecided = Medium ** Changed in: linux (Ubuntu) Importance: Undecided = Medium ** Changed in: linux (Ubuntu) Importance: Medium = High ** Changed in: linux (Ubuntu Trusty) Importance: Medium = High -- 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/1344323 Title: Trusty kernel network performance regression Status in “linux” package in Ubuntu: Fix Released Status in “linux” source package in Trusty: In Progress Bug description: SRU Justification: Impact: Reduced TCP/IP receive performance for network devices that do not split packet headers into skb linear area (e.g., mlx4). The trusty kernel has incorporated commit eff44f9cc9a02aad53d568d3ae5020b6792ae4f6 Author: Jerry Chu hk...@google.com Date: Wed Dec 11 20:53:45 2013 -0800 net-gro: Prepare GRO stack for the upcoming tunneling support which modifies the GRO frag0 optimization, but unfortunately for some cases results in calls to __skb_pull_tail for every packet being received via the GRO path. This causes a reduction in TCP receive performance (or, more accurately, an increase in CPU load for TCP receive processing, which will cause throughput reduction for CPU limited workloads). Fix: This has already been fixed in mainline in commit a50e233c50dbc881abaa0e4070789064e8d12d70 Author: Eric Dumazet eduma...@google.com Date: Sat Mar 29 21:28:21 2014 -0700 net-gro: restore frag0 optimization The fix has been backported to and verified on the trusty kernel using mlx4 devices and iperf; an increase from 7.5 to 8.5 Gb/sec was observed when adding the patch, and the relevant portion of perf captures show changes in the call paths from: 7.17%iperf [kernel.kallsyms] [k] __pskb_pull_tail | --- __pskb_pull_tail | |--48.03%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--28.53%-- napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--13.11%-- inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq to: 4.87% iperf [kernel.kallsyms] [k] skb_gro_receive | --- skb_gro_receive | |--98.13%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq Testcase: The fix was tested using mlx4 10Gb/sec network devices between two arm64 systems using iperf -s on one end and iperf -c on the other. The unmodified kernel reported approximately 7.5 Gb/sec throughput, the fixed kernel approximately 8.5 Gb/sec. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1344323/+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
[Kernel-packages] [Bug 1344323] Re: Trusty kernel network performance regression
** Also affects: linux (Ubuntu Trusty) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Trusty) Status: New = In Progress ** Changed in: linux (Ubuntu Trusty) Assignee: (unassigned) = Jay Vosburgh (jvosburgh) ** Changed in: linux (Ubuntu) Status: Incomplete = Fix Released ** Tags added: bot-stop-nagging -- 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/1344323 Title: Trusty kernel network performance regression Status in “linux” package in Ubuntu: Fix Released Status in “linux” source package in Trusty: In Progress Bug description: SRU Justification: Impact: Reduced TCP/IP receive performance for network devices that do not split packet headers into skb linear area (e.g., mlx4). The trusty kernel has incorporated commit eff44f9cc9a02aad53d568d3ae5020b6792ae4f6 Author: Jerry Chu hk...@google.com Date: Wed Dec 11 20:53:45 2013 -0800 net-gro: Prepare GRO stack for the upcoming tunneling support which modifies the GRO frag0 optimization, but unfortunately for some cases results in calls to __skb_pull_tail for every packet being received via the GRO path. This causes a reduction in TCP receive performance (or, more accurately, an increase in CPU load for TCP receive processing, which will cause throughput reduction for CPU limited workloads). Fix: This has already been fixed in mainline in commit a50e233c50dbc881abaa0e4070789064e8d12d70 Author: Eric Dumazet eduma...@google.com Date: Sat Mar 29 21:28:21 2014 -0700 net-gro: restore frag0 optimization The fix has been backported to and verified on the trusty kernel using mlx4 devices and iperf; an increase from 7.5 to 8.5 Gb/sec was observed when adding the patch, and the relevant portion of perf captures show changes in the call paths from: 7.17%iperf [kernel.kallsyms] [k] __pskb_pull_tail | --- __pskb_pull_tail | |--48.03%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--28.53%-- napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq [...] |--13.11%-- inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq to: 4.87% iperf [kernel.kallsyms] [k] skb_gro_receive | --- skb_gro_receive | |--98.13%-- tcp_gro_receive | tcp4_gro_receive | inet_gro_receive | dev_gro_receive | napi_gro_frags | mlx4_en_process_rx_cq | mlx4_en_poll_rx_cq | net_rx_action | __do_softirq Testcase: The fix was tested using mlx4 10Gb/sec network devices between two arm64 systems using iperf -s on one end and iperf -c on the other. The unmodified kernel reported approximately 7.5 Gb/sec throughput, the fixed kernel approximately 8.5 Gb/sec. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1344323/+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
