revert default to 20, for large repositories it's better to go less and have it faster.

This is still saved in user session so everyone can set high number and have it saved while logged in.

rhodecode/controllers/changelog.py

@@ -37,8 +37,7 b' from rhodecode.lib.base import BaseRepoC'
 from rhodecode.lib.helpers import RepoPage
 from rhodecode.lib.compat import json
 
-from vcs.exceptions import RepositoryError, ChangesetError, \
-ChangesetDoesNotExistError,BranchDoesNotExistError
+from vcs.exceptions import RepositoryError, ChangesetDoesNotExistError
 
 log = logging.getLogger(__name__)
 
@@ -54,7 +53,7 b' class ChangelogController(BaseRepoContro'
 
     def index(self):
         limit = 100
-        default = 40
+        default = 20
         if request.params.get('size'):
             try:
                 int_size = int(request.params.get('size'))