Date: 2004-12-10T07:52:15
Editor: OliverZeigermann <[EMAIL PROTECTED]>
Wiki: Jakarta-Slide Wiki
Page: ConcurrencyIssues
URL: http://wiki.apache.org/jakarta-slide/ConcurrencyIssues
no comment
Change Log:
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@@ -35,14 +35,41 @@
== Store ==
-Store specific parameters are also srt in Domain.xml, however
+Store specific parameters are also set in Domain.xml, however they are in the
store defintion parts either in the compound parts or inside the specific child
stores.
+
+For example to set ''cache-timeout'' in your ''simple'' store to 100 seconds
and make its child node store to defer saves you would have something similar
to this in your Domain.xml
+
+{{{<slide>
+ <namespace ...>
+ ...
+ <definition>
+ <store name="simple">
+ <parameter name="cache-timeout">100</parameter>
+ <nodestore
classname="org.apache.slide.store.txfile.TxXMLFileDescriptorsStore">
+ <parameter name="defer-saving">true</parameter>
+ ...
+ </nodestore>
+ ...
+ </store>
+
+ ...
+ </definition>
+...}}}
+
+
+
+The parameters for compound parent stores mainly effect caching as described
in ["CacheConfiguration"], but also have some impact on concurrency. E.g. if a
resource is retrieved from caches, the underlying store has no idea of this and
thus can not set a read lock. As internal caches feature a lock less isolation
similar to read committed, the effective isolation level will be a mixture of
this and the one used by the persistent store.
=== Tx File Store (standard store) ===
-The standard file store uses pessimistic locking to achieve serializable
transaction. No real deadlock detection is available, yet, only timeouts. You
can set the timeout in the configuration section of Domain.xml. Additionally,
+The standard file store uses pessimistic locking to achieve serializable
transaction. No real deadlock detection is available, yet, only timeouts. You
can set the timeouts:
- * ''defer-saving (default "false")''
* ''timeout (default 5 seconds)''
+
+You can also ask the tx file store not to execute write requests immedeately,
but at commit time. While this reduces the amount of write accesses write locks
are not immedeately acquired. In combination with deferred read requests due to
caching this may weaken the isolation of your transactions:
+
+ * ''defer-saving (default "false")''
+
== Memory Store ==
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