[Pacemaker] attrd does not update crm_master

[Andrew Beekhof]

On Mon, Jan 11, 2010 at 9:34 PM, hj lee <kerdosa at gmail.com> wrote:
>
>
> On Mon, Jan 11, 2010 at 1:22 PM, hj lee <kerdosa at gmail.com> wrote:
>>
>> Hi,
>>
>> I have a situation crm_master does not update a master score. I increased
>> log level at attrd. And I found that current value is 20000 but stored value
>> is 5. I don't know how attrd ends up this state. But attrd ignores this
>> update, so a master score does not change at all. I think the code should
>> check the stored value, not current value in memory. As long as the stored
>> value is different, then it should update. Should I create a bug?
>>
>> Thanks
>> hj
>>
>>
>> 2010-01-11 09:37:16.425570 copper2-attrd: [4649]: debug: debug3:
>> log_data_element: attrd_ipc_callback: attrd_ipc_callback <attrd_update
>> t="attrd" src="crm_attribute" task="update" attr_name="master-vmrd-res:0"
>> attr_value="20000" attr_section="status" attr_host="copper2" />
>> 2010-01-11 09:37:16.425602 copper2-attrd: [4649]: debug:
>> attrd_local_callback: update message from crm_attribute:
>> master-vmrd-res:0=20000
>> 2010-01-11 09:37:16.425611 copper2-attrd: [4649]: debug: debug2:
>> find_hash_entry: #011master-vmrd-res:0->section: status
>> 2010-01-11 09:37:16.425642 copper2-attrd: [4649]: debug: debug2:
>> log_hash_entry: Found (and updated) entry:
>> 2010-01-11 09:37:16.425651 copper2-attrd: [4649]: debug: debug2:
>> log_hash_entry: Set:     status
>> 2010-01-11 09:37:16.425658 copper2-attrd: [4649]: debug: debug2:
>> log_hash_entry: Name:    master-vmrd-res:0
>> 2010-01-11 09:37:16.425667 copper2-attrd: [4649]: debug: debug2:
>> log_hash_entry: Value:   20000
>> 2010-01-11 09:37:16.425699 copper2-attrd: [4649]: debug: debug2:
>> log_hash_entry: Timeout: (null)
>> 2010-01-11 09:37:16.425708 copper2-attrd: [4649]: debug:
>> attrd_local_callback: Supplied: 20000, Current: 20000, Stored: 5
>> 2010-01-11 09:37:16.425740 copper2-attrd: [4649]: debug: debug2:
>> attrd_local_callback: Ignoring non-change
>>
>
> Hi again,
>
> Thanks to the pacemaker log, I could browse the source code for this issue.
> The stored_value is only updated after cib_ok returned, but current is
> updated to the supplied value on request before sending update to cib. So
> this can cause the difference in current and stored value. The code compares
> only the supplied and current value. So if the cib update fails, then it
> ends up this situation! The fix will be very simple, either remove compares
> it against the stored_value or update current only after cib_ok returns.

Well spotted.  Just checked in:
   http://hg.clusterlabs.org/pacemaker/stable-1.0/rev/214f0fc258f2