| 2017-05-18 01:53:40 |
dann frazier |
bug |
|
|
added bug |
| 2017-05-18 01:55:03 |
dann frazier |
nominated for series |
|
Ubuntu Xenial |
|
| 2017-05-18 01:55:03 |
dann frazier |
bug task added |
|
linux (Ubuntu Xenial) |
|
| 2017-05-18 01:55:03 |
dann frazier |
nominated for series |
|
Ubuntu Zesty |
|
| 2017-05-18 01:55:03 |
dann frazier |
bug task added |
|
linux (Ubuntu Zesty) |
|
| 2017-05-18 01:55:03 |
dann frazier |
nominated for series |
|
Ubuntu Yakkety |
|
| 2017-05-18 01:55:03 |
dann frazier |
bug task added |
|
linux (Ubuntu Yakkety) |
|
| 2017-05-18 02:00:10 |
Brad Figg |
linux (Ubuntu): status |
New |
Incomplete |
|
| 2017-05-18 02:00:12 |
Brad Figg |
linux (Ubuntu Xenial): status |
New |
Incomplete |
|
| 2017-05-18 02:00:15 |
Brad Figg |
linux (Ubuntu Yakkety): status |
New |
Incomplete |
|
| 2017-05-18 02:00:17 |
Brad Figg |
linux (Ubuntu Zesty): status |
New |
Incomplete |
|
| 2017-05-18 14:50:07 |
dann frazier |
linux (Ubuntu): assignee |
|
dann frazier (dannf) |
|
| 2017-05-18 14:50:08 |
dann frazier |
linux (Ubuntu Xenial): assignee |
|
dann frazier (dannf) |
|
| 2017-05-18 14:50:10 |
dann frazier |
linux (Ubuntu Yakkety): assignee |
|
dann frazier (dannf) |
|
| 2017-05-18 14:50:12 |
dann frazier |
linux (Ubuntu Zesty): assignee |
|
dann frazier (dannf) |
|
| 2017-05-18 14:51:21 |
dann frazier |
description |
[Impact]
Performance is lowered for ARM >= v8.1 cpus by not taking advantage of the "Large System Extenstion" atomic instructions they provide.
Note: This config was enabled during xenial development, but was disabled to workaround a FTBFS[*] due to us not having a new enough binutils to support it. binutils was later updated in xenial, and supports these instructions.
[Test Case]
TBD
[Regression Risk]
There is a known small performance overhead for <= ARMv8.1 arm64 systems (noted in the Kconfig).
[...TBD...]
[*] https://launchpadlibrarian.net/229977996/buildlog_ubuntu-xenial-arm64.linux_4.4.0-0.5_BUILDING.txt.gz |
[Impact]
Performance is lowered for ARM >= v8.1 cpus by not taking advantage of the "Large System Extenstion" atomic instructions they provide.
Note: This config was enabled during xenial development, but was disabled to workaround a FTBFS[*] due to us not having a new enough binutils to support it. binutils was later updated in xenial, and supports these instructions.
[Test Case]
TBD
[Regression Risk]
There is a known small performance overhead for <= ARMv8.1 arm64 systems (noted in the Kconfig).
[...TBD...]
[*] https://answers.launchpad.net/~canonical-kernel-team/+archive/ubuntu/unstable/+build/8438034 |
|
| 2017-05-18 17:57:26 |
dann frazier |
description |
[Impact]
Performance is lowered for ARM >= v8.1 cpus by not taking advantage of the "Large System Extenstion" atomic instructions they provide.
Note: This config was enabled during xenial development, but was disabled to workaround a FTBFS[*] due to us not having a new enough binutils to support it. binutils was later updated in xenial, and supports these instructions.
[Test Case]
TBD
[Regression Risk]
There is a known small performance overhead for <= ARMv8.1 arm64 systems (noted in the Kconfig).
[...TBD...]
[*] https://answers.launchpad.net/~canonical-kernel-team/+archive/ubuntu/unstable/+build/8438034 |
[Impact]
Performance is lowered for ARM >= v8.1 cpus by not taking advantage of the "Large System Extenstion" atomic instructions they provide.
Note: This config was enabled during xenial development, but was disabled to workaround a FTBFS[*] due to us not having a new enough binutils to support it. binutils was later updated in xenial, and supports these instructions.
[Test Case]
grep CONFIG_ARM64_LSE_ATOMICS=y /boot/config-$(uname -r)
[Regression Risk]
There is a known small performance overhead for < ARMv8.1 arm64 systems (noted in the Kconfig). To mitigate the risk of runtime or build failures, this should be tested on both ARMv8 and >= ARMv8.1 systems.
[*] https://answers.launchpad.net/~canonical-kernel-team/+archive/ubuntu/unstable/+build/8438034 |
|
| 2017-05-18 17:59:00 |
dann frazier |
description |
[Impact]
Performance is lowered for ARM >= v8.1 cpus by not taking advantage of the "Large System Extenstion" atomic instructions they provide.
Note: This config was enabled during xenial development, but was disabled to workaround a FTBFS[*] due to us not having a new enough binutils to support it. binutils was later updated in xenial, and supports these instructions.
[Test Case]
grep CONFIG_ARM64_LSE_ATOMICS=y /boot/config-$(uname -r)
[Regression Risk]
There is a known small performance overhead for < ARMv8.1 arm64 systems (noted in the Kconfig). To mitigate the risk of runtime or build failures, this should be tested on both ARMv8 and >= ARMv8.1 systems.
[*] https://answers.launchpad.net/~canonical-kernel-team/+archive/ubuntu/unstable/+build/8438034 |
[Impact]
Performance is lowered for ARM >= v8.1 cpus by not taking advantage of the "Large System Extenstion" atomic instructions they provide.
Note: This config was enabled during xenial development, but was disabled to workaround a FTBFS[*] due to us not having a new enough binutils to support it. binutils was later updated in xenial, and supports these instructions.
[Test Case]
grep CONFIG_ARM64_LSE_ATOMICS=y /boot/config-$(uname -r)
[Regression Risk]
There is a known small performance overhead for < ARMv8.1 arm64 systems (noted in the Kconfig). To mitigate the risk of runtime or build failures, this should be tested on both ARMv8 and >= ARMv8.1 systems, to exercise both code paths.
[*] https://answers.launchpad.net/~canonical-kernel-team/+archive/ubuntu/unstable/+build/8438034 |
|
| 2017-05-18 20:28:27 |
dann frazier |
linux (Ubuntu): status |
Incomplete |
In Progress |
|
| 2017-05-18 20:28:37 |
dann frazier |
linux (Ubuntu Xenial): status |
Incomplete |
Confirmed |
|
| 2017-05-18 20:28:39 |
dann frazier |
linux (Ubuntu Yakkety): status |
Incomplete |
Confirmed |
|
| 2017-05-18 20:28:42 |
dann frazier |
linux (Ubuntu Zesty): status |
Incomplete |
Triaged |
|
| 2017-05-18 20:28:44 |
dann frazier |
linux (Ubuntu Yakkety): status |
Confirmed |
Triaged |
|
| 2017-05-18 20:28:46 |
dann frazier |
linux (Ubuntu Xenial): status |
Confirmed |
Triaged |
|
| 2017-05-19 19:22:24 |
dann frazier |
linux (Ubuntu Xenial): status |
Triaged |
Won't Fix |
|
| 2017-05-19 19:22:26 |
dann frazier |
linux (Ubuntu): status |
In Progress |
Fix Committed |
|
| 2017-05-19 19:22:30 |
dann frazier |
linux (Ubuntu Yakkety): status |
Triaged |
Won't Fix |
|
| 2017-05-19 19:22:32 |
dann frazier |
linux (Ubuntu Zesty): status |
Triaged |
Won't Fix |
|
| 2017-07-12 12:13:16 |
Launchpad Janitor |
linux (Ubuntu): status |
Fix Committed |
Fix Released |
|
