K 10
svn:author
V 7
glebius
K 8
svn:date
V 27
2012-02-16T19:10:01.010663Z
K 7
svn:log
V 1004
Refactor the name hash and the ID hash, that are used to address nodes:

- Make hash sizes growable, to satisfy users running large mpd
  installations, having thousands of nodes.
- NG_NAMEHASH() proved to give a very bad distribution in real life
  name sets, while generic hash32_str(name, HASHINIT) proved to give
  an even one, so you the latter for name hash.
- Do not store unnamed nodes in slot 0 of name hash, no reason for that.
- Use the ID hash in cases when we need to run through all nodes: the
  NGM_LISTNODES command and in the vnet_netgraph_uninit().
- Implement NGM_LISTNODES and NGM_LISTNAMES as separate code, the former
  iterates through the ID hash, and the latter through the name hash.
- Keep count of all nodes and of named nodes, so that we don't need
  to count nodes in NGM_LISTNODES and NGM_LISTNAMES. The counters are
  also used to estimate whether we need to grow hashes.
- Close a race between two threads running ng_name_node() assigning same
  name to different nodes.

END