In the repair subsystem, it is necessary to acquire several extra
properties of nodes that are holding pieces of things or may be
selected to hold pieces. We need to know if a node is 'online' (the
definition of "online" may change somewhat depending on the situation),
if a node is in the process of graceful exit, and whether a node is
suspended. We can't just filter out nodes with all of these properties,
because sometimes we need to know properties about nodes even when the
nodes are suspended or gracefully exiting.
I thought the best way to do this was to add fields to SelectedNode,
and (to avoid any confusion) arrange for the added fields to be
populated wherever SelectedNode is returned, whether or not the new
fields are necessarily going to be used.
If people would rather I use a separate type from SelectedNode, I can do
that instead.
Change-Id: I7804a0e0a15cfe34c8ff47a227175ea5862a4ebc
All the files in uploadselection are (in fact) related to generic node selection, and used not only for upload,
but for download, repair, etc...
Change-Id: Ie4098318a6f8f0bbf672d432761e87047d3762ab
Currently nodeselection package only contained state for uploads, move
these to a subpackage, such that we can make another "downloadselection"
for downloads. Then move selection logic from overlay to nodeselection.
Change-Id: I0fc42bcae3a29db2728dae9f3863b1e95bf5165b
Currently node selection cache is biased towards the same subnet. This
implements static node selection for distinct such that it selects with
equal probability subnets rather than id-s.
This is mostly a copy paste + modifications from previous node selection
state.
Change-Id: Ia5c0aaf68e7feca78fbbd7352ad369fcb77c3a05
