Open Stack

Hi,

I submited a modified patch set as follows.
In addition, I added test codes for this patch.

>   1. Set an integer cookie value to taas flows.
>      Maybe all "1" for short term tentative value.
>   2. Modify the cleanup logic in ovs-agent not to delete flows
>      which have a reserved integer cookie value.

https://review.openstack.org/#/c/257285/
https://review.openstack.org/#/c/257286/

Thanks,
KAZ


From: Soichi Shigeta <shigeta.soichi at jp.fujitsu.com>
Subject: Re: [openstack-dev] [neutron][taas] neutron ovs-agent deletes taas flows
Date: Thu, 17 Dec 2015 09:28:10 +0900

> 
>  Thank you for your helpful comments.
> 
>  I'd like to update my proposal as follows:
> 
>   1. Set an integer cookie value to taas flows.
>      Maybe all "1" for short term tentative value.
>   2. Modify the cleanup logic in ovs-agent not to delete flows
>      which have a reserved integer cookie value.
> 
> 
>> Sorry, that I don't see this earlier. Yes, cookies have integer
>> values, so
>> we won't be able to set string there. May be we can have a reserved
>> integer
>> cookie value for a project like all "1".
>>
>> I won't support idea of modifying cleanup logic not to drop 0x0
>> cookies.
>> During implementation of graceful restart it was not dropped at first,
>> but
>> I get rid of it as having a lot of flows not related to anything was
>> not
>> desirable, so we should try to avoid it here, too.
>>
>> On Wed, Dec 16, 2015 at 7:46 AM, Soichi Shigeta <
>> shigeta.soichi at jp.fujitsu.com> wrote:
>>
>>>
>>>     o) An idea to fix:
>>>>
>>>>        1. Set "taas" stamp(*) to taas flows.
>>>>        2. Modify the cleanup logic in ovs-agent not to delete entries
>>>>           stamped as "taas".
>>>>
>>>>        * Maybe a static string.
>>>>          If we need to use a string which generated dynamically
>>>>          (e.g. uuid), API to interact with ovs-agent is required.
>>>>
>>>>
>>>    Last week I proposed to set a static string (e.g. "taas") as cookie
>>>    of flows created by taas agent.
>>>
>>>    But I found that the value of a cookie should not be a string,
>>>    but an integer.
>>>
>>>    At line 187 in
>>> "neutron/neutron/plugins/ml2/drivers/openvswitch/agent/ovs_neutron_agent.py":
>>>    self.agent_uuid_stamp = uuid.uuid4().int & UINT64_BITMASK
>>>
>>>    In case of we set an integer value to cookie, coordination
>>>    (reservation of range) is required to avoid conflict of cookies with
>>>    other neutron sub-projects.
>>>
>>>    As an alternative (*** short term ***) solution, my idea is:
>>>    Modify the clean up logic in ovs agent not to delete flows whose
>>>    "cookie = 0x0".
>>>    Because old flows created by ovs agent have an old stamp, "cookie =
>>>    0x0" means it was created by other than ovs agent.
>>>
>>>    # But, this idea has a disadvantage:
>>>      If there are flows which have been created by older version of ovs
>>>      agent, they can not be cleaned.
>>>
> 
> 
> 
> __________________________________________________________________________
> OpenStack Development Mailing List (not for usage questions)
> Unsubscribe:
> OpenStack-dev-request at lists.openstack.org?subject:unsubscribe
> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev