Open 1.7.x backport branch for the r1527103 group.

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-r1527103@1527110 13f79535-47bb-0310-9956-ffa450edef68
Merged r1527103,-5 from /trunk and resolved the tree conflict.

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-r1527103@1527112 13f79535-47bb-0310-9956-ffa450edef68
* 1.7.x/STATUS:
   propose r1527112 (aka r1527103, r1527105) for backport

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-r1527103@1527114 13f79535-47bb-0310-9956-ffa450edef68
On the 1.7.x-r1527103 branch: Sync with branches/1.7.x to resolve conflict

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-r1527103@1532095 13f79535-47bb-0310-9956-ffa450edef68
Opening bugfix branch to backport a 1.8 commit performance fix to 1.7.x.

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-fsfs-commit@1536760 13f79535-47bb-0310-9956-ffa450edef68
Backport of the code limiting the time spent walking the node history
when committing a file.

As it turns out, some users make scripted commits that not only create
deep histories for individual files but create many of those files with
the exact same depths of history, i.e. number of changes.

Without this patch, committing the e.g. 65536th change to this set of
files will take hours instead of the usual seconds.  With this patch
we are down to a few minutes.

* subversion/libsvn_fs_fs/fs_fs.c
  (SVN_FS_FS_MAX_DELTIFICATION_WALK): define limit to the effort we spend
                                      on finding a delta base
  (choose_delta_base): don't attempt walks longer than the defined limit

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x-fsfs-commit@1536790 13f79535-47bb-0310-9956-ffa450edef68
Merge the 1.7.x-r1527103 branch:

 * r1527112
   Fix OOM with concurrent requests right after threaded server start.
   Changes:
     This was a common condition in my load tests.  Affects threaded
     servers only.  Apache will just respawn a new worker process.
   Branch:
     ^/subversion/branches/1.7.x-r1527103
   Votes:
     +1: stefan2, brane, breser


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x@1541379 13f79535-47bb-0310-9956-ffa450edef68
Merge the 1.7.x-fsfs-commit branch:

 * r1536790
   Limit the time spent in committing files with deep change histories
   Justification:
      The problem has been observed in the real world with certain
      committs taking hours instead of seconds.  This patch sets a
      firm limit to the internal processing effort and cuts it down
      from several hours to a few minutes.
   Branch:
     ^/subversion/branches/1.7.x-fsfs-commit
   Votes:
     +1: stefan2, brane, breser


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.7.x@1541381 13f79535-47bb-0310-9956-ffa450edef68