[Linux-ha-dev] Large delays in sending ordered HA messages
alanr at unix.sh
Wed Oct 6 13:36:47 MDT 2004
Guochun Shi wrote:
> At 11:42 AM 10/6/2004 +0200, you wrote:
>>On 2004-10-05T23:27:23, Guochun Shi <gshi at ncsa.uiuc.edu> wrote:
>>>I have a simple way to accomplish the goal: let's say the last
>>>heartbeat seq number recorded for a node (node A) in heartbeat is
>>>seq_last, then any ordered message from node A with a heartbeat seq
>>>number > seq_last can be delivered to an application immediately ---
>>>this is the first ordered message delivered. Later ordered message
>>>delivery can be computed through the ordered seq. The reason the first
>>>ordered message can be delivered in that way is that any message with
>>>heartbeat seq number > seq_last will be received (unless heartbeat
>>>retransmitting mechanism is broken) therefore we will not miss any
>>>later ordered message. Messages with seq less than seq_last ---- out
>>>ordered or retransmitted messages-- will be discarded.
>>Of course, you can only do this for the first ordered message from a
>>node after a startup (or after a node returns after having dropped out
> Once we are done with the first ordered message, we can order subsequent messages using the ordered-seq number.
>>But yes, this should work.
This sounds like a simple fix to a problem that looked complicated when I
last looked at it.
Good Job Guochun!
Please code this up and test it. Check for memory leaks (obviously ;-)),
and then commit it.
Alan Robertson <alanr at unix.sh>
"Openness is the foundation and preservative of friendship... Let me claim
from you at all times your undisguised opinions." - William Wilberforce
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