ignite-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Александр Меньшиков <sharple...@gmail.com>
Subject Re: Sort nodes in the ring in order to minimize the number of reconnections
Date Mon, 23 Jan 2017 13:56:01 GMT
Igor, I have thought about approach what you are talking about. It need add
new field named like "sortedNodes" with custom ordering, which will have
the same items as "nodes" field, because "nodes" has being used with
default ordering in other methods. It have this advantages:

1. Method "nextNode" will look simpler.
2. Method "nextNode" will work faster, because using of method
TreeSet#higher() will be available. But that possibility had not been used
in original code. And I don't why.

But also have some disadvantages because new field "sortedNodes" will be
strongly connected with "nodes":
1. It need copy-paste all code, which modifies "nodes" in 4 other methods.
It will decrease maintainability.
2. Field "nodes" is being used with "copy-on-write" algorithm. So state of
"nodes" and "sortedNodes" can be inconsistent. Maybe it's okay, in fact I
just don't know. But any way in future it may become a problem.

So my opinion is that "presorted" approach can work a little bit faster
(number of nodes never can't be so big that O(log n) became more faster
than O(n)), but code complexity will been increased, because it will add
one logic connection inside the whole class "TcpDiscoveryNodesRing".

Yakov, can you settle our argument?

2017-01-20 16:30 GMT+03:00 Игорь Г <frenel@gmail.com>:

> Alexander, maybe you should use presorted collection in
> TcpDiscoveryNodesRing.nextNode instead of iterating through unsorted one
> every time?

  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message