Public bug reported:
This is a public version of https://bugs.launchpad.net/bugs/2028897
Backport:
bc9d3a9f2afc (net: dst: Switch to rcuref_t reference counting, 2023-03-23)
d288a162dd1c (net: dst: Prevent false sharing vs. dst_entry:: __refcnt,
2023-03-23)
e5ab9eff46b0 (atomics: Provide atomic_add_negative() variants, 2023-03-23)
ee1ee6db0779 (atomics: Provide rcuref - scalable reference counting, 2023-03-23)
merged in 6.4 to jammy.
[Impact]
Address a bottleneck in the networking code related to struct dst_entry
reference count, which results in networking performance loss with large number
of connections, by adding rcuref as a scalable alternative solution.
Developers report in the patch: The overall gain of both changes for
localhost memtier ranges from 1.2X to 3.2X and from +2% to %5% range for
networked operations on a 1Gb connection. A micro benchmark which
enforces maximized concurrency shows a gain between 1.2X and 4.7X.
[Fix]
Upstream patch:
bc9d3a9f2afc (net: dst: Switch to rcuref_t reference counting, 2023-03-23)
d288a162dd1c (net: dst: Prevent false sharing vs. dst_entry:: __refcnt,
2023-03-23)
e5ab9eff46b0 (atomics: Provide atomic_add_negative() variants, 2023-03-23)
ee1ee6db0779 (atomics: Provide rcuref - scalable reference counting,
2023-03-23)
[Test Plan]
I have tested this code.
[Where problems could occur]
TODO
** Affects: linux (Ubuntu)
Importance: Undecided
Status: New
** Affects: linux (Ubuntu Jammy)
Importance: Undecided
Status: New
** Also affects: linux (Ubuntu Jammy)
Importance: Undecided
Status: New
--
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/2058481
Title:
[SPR] Networking performance fix for concurrency with the dst_entry
data structure
Status in linux package in Ubuntu:
New
Status in linux source package in Jammy:
New
Bug description:
This is a public version of https://bugs.launchpad.net/bugs/2028897
Backport:
bc9d3a9f2afc (net: dst: Switch to rcuref_t reference counting, 2023-03-23)
d288a162dd1c (net: dst: Prevent false sharing vs. dst_entry:: __refcnt,
2023-03-23)
e5ab9eff46b0 (atomics: Provide atomic_add_negative() variants, 2023-03-23)
ee1ee6db0779 (atomics: Provide rcuref - scalable reference counting,
2023-03-23)
merged in 6.4 to jammy.
[Impact]
Address a bottleneck in the networking code related to struct dst_entry
reference count, which results in networking performance loss with large number
of connections, by adding rcuref as a scalable alternative solution.
Developers report in the patch: The overall gain of both changes for
localhost memtier ranges from 1.2X to 3.2X and from +2% to %5% range
for networked operations on a 1Gb connection. A micro benchmark which
enforces maximized concurrency shows a gain between 1.2X and 4.7X.
[Fix]
Upstream patch:
bc9d3a9f2afc (net: dst: Switch to rcuref_t reference counting, 2023-03-23)
d288a162dd1c (net: dst: Prevent false sharing vs. dst_entry:: __refcnt,
2023-03-23)
e5ab9eff46b0 (atomics: Provide atomic_add_negative() variants, 2023-03-23)
ee1ee6db0779 (atomics: Provide rcuref - scalable reference counting,
2023-03-23)
[Test Plan]
I have tested this code.
[Where problems could occur]
TODO
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2058481/+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
