Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-03-07 Thread Jason Baron
On 03/05/2015 04:15 AM, Ingo Molnar wrote: * Jason Baron jba...@akamai.com wrote: 2) We are using the wakeup in this case to 'assign' work more permanently to the thread. That is, in the case of a listen socket we then add the connected socket to the woken up threads local set of epoll

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-03-05 Thread Jason Baron
On 03/05/2015 04:15 AM, Ingo Molnar wrote: * Jason Baron jba...@akamai.com wrote: 2) We are using the wakeup in this case to 'assign' work more permanently to the thread. That is, in the case of a listen socket we then add the connected socket to the woken up threads local set of epoll

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-03-05 Thread Ingo Molnar
* Jason Baron jba...@akamai.com wrote: 2) We are using the wakeup in this case to 'assign' work more permanently to the thread. That is, in the case of a listen socket we then add the connected socket to the woken up threads local set of epoll events. So the load persists past the wake

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-03-04 Thread Ingo Molnar
* Andrew Morton a...@linux-foundation.org wrote: On Fri, 27 Feb 2015 17:01:32 -0500 Jason Baron jba...@akamai.com wrote: I don't really understand the need for rotation/round-robin. We can solve the thundering herd via exclusive wakeups, but what is the point in choosing to

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-03-04 Thread Jason Baron
On 03/04/2015 07:02 PM, Ingo Molnar wrote: * Andrew Morton a...@linux-foundation.org wrote: On Fri, 27 Feb 2015 17:01:32 -0500 Jason Baron jba...@akamai.com wrote: I don't really understand the need for rotation/round-robin. We can solve the thundering herd via exclusive wakeups, but what

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-03-01 Thread Jason Baron
On 02/27/2015 04:31 PM, Jonathan Corbet wrote: On Fri, 27 Feb 2015 13:10:34 -0800 Andrew Morton a...@linux-foundation.org wrote: I don't really understand the need for rotation/round-robin. We can solve the thundering herd via exclusive wakeups, but what is the point in choosing to wake the

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-02-27 Thread Jonathan Corbet
On Fri, 27 Feb 2015 13:10:34 -0800 Andrew Morton a...@linux-foundation.org wrote: I don't really understand the need for rotation/round-robin. We can solve the thundering herd via exclusive wakeups, but what is the point in choosing to wake the task which has been sleeping for the longest

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-02-27 Thread Jason Baron
On 02/27/2015 04:10 PM, Andrew Morton wrote: On Wed, 25 Feb 2015 11:27:04 -0500 Jason Baron jba...@akamai.com wrote: Libenzi inactive eventpoll appears to be without a dedicated maintainer since 2011 or so. Is there anyone who knows the code and its usages in detail and does final ABI

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-02-27 Thread Andrew Morton
On Wed, 25 Feb 2015 11:27:04 -0500 Jason Baron jba...@akamai.com wrote: Libenzi inactive eventpoll appears to be without a dedicated maintainer since 2011 or so. Is there anyone who knows the code and its usages in detail and does final ABI decisions on eventpoll - Andrew, Al or Linus?

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-02-27 Thread Andrew Morton
On Fri, 27 Feb 2015 17:01:32 -0500 Jason Baron jba...@akamai.com wrote: I don't really understand the need for rotation/round-robin. We can solve the thundering herd via exclusive wakeups, but what is the point in choosing to wake the task which has been sleeping for the longest

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-02-25 Thread Jason Baron
On 02/25/2015 02:38 AM, Ingo Molnar wrote: * Jason Baron jba...@akamai.com wrote: Hi, When we are sharing a wakeup source among multiple epoll fds, we end up with thundering herd wakeups, since there is currently no way to add to the wakeup source exclusively. This series introduces a

[PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-02-24 Thread Jason Baron
Hi, When we are sharing a wakeup source among multiple epoll fds, we end up with thundering herd wakeups, since there is currently no way to add to the wakeup source exclusively. This series introduces a new EPOLL_ROTATE flag to allow for round robin exclusive wakeups. I believe this patch

Re: [PATCH v3 0/3] epoll: introduce round robin wakeup mode

2015-02-24 Thread Ingo Molnar
* Jason Baron jba...@akamai.com wrote: Hi, When we are sharing a wakeup source among multiple epoll fds, we end up with thundering herd wakeups, since there is currently no way to add to the wakeup source exclusively. This series introduces a new EPOLL_ROTATE flag to allow for round