Fetch running-routers.

Split logic to initiate dirfetch, running-routers fetch, and
descriptor post.  arma: There are some XXXs here that raise design
questions which we should solve before the next release.

The biggest problem is this: Right now, the directory is about 50X as
large as running-routers uncompressed, and about 36X as large
compressed.  Assuming:

    - everybody gets the compressed version of everything,

    - everybody gets cached directories from random dirservers and
      uncached r-r from authdirservers

    - everybody downloads r-r at the same rate they now download dirs,

then using r-r from will *increase* authdirserver directory bandwidth usage
if there are significantly more caches than authdirservers.

I think it's safe to leave this in for now, since there aren't 3x36 caching
dirservers, but we should make everybody with a dirport cache running-routers
soon.  But I could be wrong.


svn:r2872

1 files changed, 5 insertions, 1 deletions

diff --git a/doc/TODO b/doc/TODO
index cb4e4cc76..5bd7dae11 100644
--- a/doc/TODO
+++ b/doc/TODO
@@ -24,7 +24,11 @@ N  - clients now have certs, which means we warn when their certs have
      o Function to generate the contents for a torrc file.
      o Function to safely replace a torrc file.
 R  - fix print_usage()
-   - Download and use running-routers
+   . Download and use running-routers
+     o Code to download running-routers
+     - Decouple DirFetchPeriod, StatusFetchPeriod, DirPostPeriod.
+     - Do we really want to send the clients to the authdirservers for
+       running-routers so often?
 R  - document signals in man page
    o Check for hibernation on startup, hup, etc.
 N  - Test hibernation a lot.