Make RDBMS cache-size configurable.

git-svn-id: http://svn.roundup-tracker.org/svnroot/roundup/roundup/trunk@4166 57a73879-2fb5-44c3-a270-3262357dd7e2

diff --git a/roundup/backends/rdbms_common.py b/roundup/backends/rdbms_common.py
index 76243d2249d48b0d80c72f78fb4c4af774f19573..31aa0ac0e4e69795740e228cdc7dcc0555ee0e37 100644 (file)
--- a/roundup/backends/rdbms_common.py
+++ b/roundup/backends/rdbms_common.py
@@ -71,9 +71,6 @@ except ImportError:
 from sessions_rdbms import Sessions, OneTimeKeys
 from roundup.date import Range
 
-# number of rows to keep in memory
-ROW_CACHE_SIZE = 100
-
 # dummy value meaning "argument not passed"
 _marker = []
 
@@ -108,7 +105,7 @@ class Database(FileStorage, hyperdb.Database, roundupdb.Database):
 
         - some functionality is specific to the actual SQL database, hence
           the sql_* methods that are NotImplemented
-        - we keep a cache of the latest ROW_CACHE_SIZE row fetches.
+        - we keep a cache of the latest N row fetches (where N is configurable).
     """
     def __init__(self, config, journaltag=None):
         """ Open the database and load the schema from it.
@@ -125,6 +122,7 @@ class Database(FileStorage, hyperdb.Database, roundupdb.Database):
 
         # keep a cache of the N most recently retrieved rows of any kind
         # (classname, nodeid) = row
+        self.cache_size = config.RDBMS_CACHE_SIZE
         self.cache = {}
         self.cache_lru = []
         self.stats = {'cache_hits': 0, 'cache_misses': 0, 'get_items': 0,
@@ -1057,7 +1055,7 @@ class Database(FileStorage, hyperdb.Database, roundupdb.Database):
         self.cache[key] = node
         # update the LRU
         self.cache_lru.insert(0, key)
-        if len(self.cache_lru) > ROW_CACHE_SIZE:
+        if len(self.cache_lru) > self.cache_size:
             del self.cache[self.cache_lru.pop()]
 
         if __debug__:

diff --git a/roundup/configuration.py b/roundup/configuration.py
index 4fa4c942758698717493e3e29cb17e61bcb9d33f..8d03f7bb3e299752864a3c37e96f57ee99287130 100644 (file)
--- a/roundup/configuration.py
+++ b/roundup/configuration.py
@@ -370,7 +370,7 @@ class OctalNumberOption(Option):
 
 class NullableOption(Option):
 
-    """Option that is set to None if it's string value is one of NULL strings
+    """Option that is set to None if its string value is one of NULL strings
 
     Default nullable strings list contains empty string only.
     There is constructor parameter allowing to specify different nullables.
@@ -592,8 +592,10 @@ SETTINGS = (
         (NullableOption, 'read_default_group', 'roundup',
             "Name of the group to use in the MySQL defaults file (.my.cnf).\n"
             "Only used in MySQL connections."),
+        (IntegerNumberOption, 'cache_size', '100',
+            "Size of the node cache (in elements)"),
     ), "Settings in this section are used"
-        " by Postgresql and MySQL backends only"
+        " by RDBMS backends only"
     ),
     ("logging", (
         (FilePathOption, "config", "",
@@ -874,7 +876,7 @@ class Config:
             _options.append(_name)
         # (section, name) key is used for writing .ini file
         self.options[(_section, _name)] = option
-        # make the option known under all of it's A.K.A.s
+        # make the option known under all of its A.K.A.s
         for _name in option.aliases:
             self.options[_name] = option