About replication

forum_thread

Master database switching to read-only mode, possibly caused by slave failure

We had a database failure causing a production outage. Both master and slave databases have failed, slave became unresponsive and the master switched to read-only mode. By the look of it the slave database failed first and possibly caused the master to switch to read-only mode. The sequence of events was: ... 19:25:59 #4 store] Database '/opt/objectdb/db/$replication/contextspace.odb' is closed by 30752@hardhead We did ... which certainly rule out some options. The replication is implemented by a simple open socket between the master and the ...

 
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ObjectDB Object Database Features

ObjectDB provides a rich set of features, many of them as the result of supporting the JPA and JDO APIs.... Replication (Cluster) Master-Slave replication (clustering) with unlimited number of slave nodes. ...

 
issue

Server out of memory exceptions

I've started to get memory exceptions on objectdb instances running as a server. The objectdb log reports this as: ... about by fishing for the problem rather than a structured replication. As the real problem only presents itself after a few days the test ...

 
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Performance tuning, best practices

we have a system where we serve from a host process around 200 clients connected via webSockets (Jetty). The core process is running on a dedicated Windows 2012 server with 16 GByte RAM and 8 processor cores.  What is strange for us is that max 20% of the cpu resources are used and the IO subsystem is at maximum 30% of activity under heavy load but database queries are let's say not at the speed we would expect. We have currently 20.000.000 objects in the database, our configuration settings are: ... enabled="true" />   <!--   <replication url="objectdb://localhost/test.odb;user=admin;password=admin" /> ...

 
issue

Unable to stop server after starting in SSL mode

ObjectDB server starts & stops fine in non-SSL mode using start & stop shell scripts. ObjectDB server starts fine in SSL mode using start script but throws error and does not stop using stop shell script. Non-SSL mode server start/stop output: ObjectDB Server started on port 7032. ObjectDB Server stopped. SSL mode server start output: ObjectDB Server (SSL) started on port 7032. SSL mode server stop output: ... path = "/opt/tomcat7/xxx" /> <!-- <replication url="objectdb://localhost/test.odb;user=admin;password=admin" ...

 
forum_thread

significant performance decrease

we are using objected in embedded mode (on OS X and WINDOWS). The database increased now to around 400000 entities of one class (database file size around 1.5 GByte). The response time of standard queries increased with this database size to an unacceptable rate (several seconds compared to around 30% when the number of entities was just half of the current). We tried to optimize the cache settings, current objectdb.conf is: <!-- ObjectDB Configuration --> <objectdb> ... path = "$objectdb/db" /> <!-- <replication url="objectdb://localhost/test.odb;user=admin;password=admin" ...

 
forum_thread

ObjectDb Supports Clustering of Servers?

Hi,     I am new to ObjectDb. we have a scenario where we deploy the same application in more than one linux (Jobss) servers. In this case user request can go to any server depends on the availability of the servers (This is for load balancing ). As of now we are using Oracle + Hibernate + JPA , as Oracle is shared data there was no problem. ... 10:17 ObjectDB replication is described on this manual page . You can use it for a ...

 
issue

NullPointerException in __odbGetNumMember

Hi,   hi, When deleting an entity "Mitglied" -> everything works fine. Trying to delete another one (in a separate transaction) always causes a NullPointer Exception in __odbGetNumMember line 1 of the enhanced Mitglied class. I am unable to replicate it in a simple testcase but it always happens in our implementation. I am posting the stack trace in the hope that it'll help to figure what's going wrong: Bug Version: 2.3.6 Priority: Normal Status: Closed Replies: 6 Type:  Bug ...

 
issue

Issue with DISTINCT Select

It is getting more and more frustrating :( We've introduced distinct select instead of regular selection in our code (no changes else) and suddenly receive invalid identifiers in queries exceptions in various queries. Here's the stacktrace: Bug Version: Priority: Normal Status: Closed Replies: 12 Type:  Bug ...

 
forum_thread

Embedded & Activation & Scalation

Hi there, Our app is highly scalable and can be distributed among multiple processes on multiple machines. ObjectDB Server is not really scalable right now and would be a SPOF for our application. So, we'd like to embedded odb into each instance instead for now and point each to the same database folder, however I've got a few questions I couldn't find answers for: ... Server can handle very high load, especially if you use replication and route READ operations to slave servers. Of course, some NoSQL ...