caches: use repo.lru based Dict cache. This LRUDict uses Timing Algo to not have to use locking

for the LRU implementation, this it's safer to use for dogpile. We used it before with beaker, so it's
generally more stable.

pkgs/python-packages.nix

@@ -791,17 +791,6 b' self: super: {'
       license = [ pkgs.lib.licenses.bsdOriginal ];
     };
   };
-  "lru-dict" = super.buildPythonPackage {
-    name = "lru-dict-1.1.6";
-    doCheck = false;
-    src = fetchurl {
-      url = "https://files.pythonhosted.org/packages/00/a5/32ed6e10246cd341ca8cc205acea5d208e4053f48a4dced2b1b31d45ba3f/lru-dict-1.1.6.tar.gz";
-      sha256 = "1k2lhd4dpl6xa6iialbwx4l6bkdzxmzhygms39pvf19x1rk5fm1n";
-    };
-    meta = {
-      license = [ pkgs.lib.licenses.mit ];
-    };
-  };
   "lxml" = super.buildPythonPackage {
     name = "lxml-3.7.3";
     doCheck = false;
@@ -1690,7 +1679,6 b' self: super: {'
       self."billiard"
       self."kombu"
       self."lxml"
-      self."lru-dict"
       self."mako"
       self."markdown"
       self."markupsafe"

requirements.txt

@@ -31,7 +31,6 b' jinja2==2.9.6'
 billiard==3.5.0.3
 kombu==4.2.0
 lxml==3.7.3
-lru-dict==1.1.6
 mako==1.0.7
 markdown==2.6.11
 markupsafe==1.0.0

rhodecode/lib/memory_lru_dict.py

@@ -25,15 +25,8 b' and the state of LRU dict.'
 inrae.cache is licensed under LRUDict is licensed under ZPL license
 This software is Copyright (c) Zope Corporation (tm) and
 Contributors. All rights reserved.
-
-TODO: marcink, we might think of replacing the LRUDict with lru-dict library
-written in C.
+"""
 
-eg difference in speed:
-
-    LRUDictC  Time : 0.00025 s, Memory : 110592 Kb
-    LRUDict   Time : 0.00369 s, Memory : 147456 Kb
-"""
 import logging
 
 from repoze.lru import LRUCache
@@ -44,8 +37,10 b' log = logging.getLogger(__name__)'
 
 
 class LRUDict(LRUCache):
-    """ Wrapper to provide partial dict access
     """
+    Wrapper to provide partial dict access
+    """
+
     def __setitem__(self, key, value):
         return self.put(key, value)
 

rhodecode/lib/rc_cache/backends.py

@@ -28,7 +28,8 b' from dogpile.cache.backends import file '
 from dogpile.cache.backends import redis as redis_backend
 from dogpile.cache.backends.file import NO_VALUE, compat, FileLock
 from dogpile.cache.util import memoized_property
-from lru import LRU as LRUDict
+
+from rhodecode.lib.memory_lru_dict import LRUDict, LRUDictDebug
 
 
 _default_max_size = 1024
@@ -41,14 +42,12 b' class LRUMemoryBackend(memory_backend.Me'
 
     def __init__(self, arguments):
         max_size = arguments.pop('max_size', _default_max_size)
-        callback = None
-        if arguments.pop('log_max_size_reached', None):
-            def evicted(key, value):
-                log.debug(
-                    'LRU: evicting key `%s` due to max size %s reach', key, max_size)
-            callback = evicted
 
-        arguments['cache_dict'] = LRUDict(max_size, callback=callback)
+        LRUDictClass = LRUDict
+        if arguments.pop('log_key_count', None):
+            LRUDictClass = LRUDictDebug
+
+        arguments['cache_dict'] = LRUDictClass(max_size)
         super(LRUMemoryBackend, self).__init__(arguments)
 
     def delete(self, key):
@@ -111,9 +110,9 b' class CustomLockFactory(FileLock):'
                         # waited to much time on a lock, better fail than loop for ever
                         log.error('Failed to acquire lock on %s file', self.filename)
                         raise
-
-                    log.debug('Failed to acquire lock, retry in 0.03')
-                    gevent.sleep(0.03)
+                    timeout = 0.03
+                    log.debug('Failed to acquire lock, retry in %ss', timeout)
+                    gevent.sleep(timeout)
 
         fcntl.flock = gevent_flock
         return fcntl

setup.py

@@ -182,8 +182,8 b' setup('
             'rc-ssh-wrapper=rhodecode.apps.ssh_support.lib.ssh_wrapper:main',
         ],
         'beaker.backends': [
-            'memorylru_base=rhodecode.lib.memory_lru_debug:MemoryLRUNamespaceManagerBase',
-            'memorylru_debug=rhodecode.lib.memory_lru_debug:MemoryLRUNamespaceManagerDebug'
+            'memorylru_base=rhodecode.lib.memory_lru_dict:MemoryLRUNamespaceManagerBase',
+            'memorylru_debug=rhodecode.lib.memory_lru_dict:MemoryLRUNamespaceManagerDebug'
         ]
     },
 )