Collecting data related metrics using JMX MBeans

One element of sizing the servers for the IBM ELM solution is the current and projected data scale (along with data shape, user scale and workload). There are also recommended artifact limits to stay within to keep an application performing well. There are a few different MBeans that will help keep track of data counts.

Item Count Details MBean

This bean will list several objects of various types (i.e. different typeName values), such as com.ibm.team.workitem.Attachment when collected for the Engineering Workflow Management (EWM) application. Each object collected has several attributes with those of prime interest being:

• itemTypeName - the name of the type of item being counted, e.g. com.ibm.team.workitem.Attachment, com.ibm.team.workitem.WorkItem, com.ibm.team.vvc.ChangeSet
• noOfContents - how many items of this type exist in the application's repository
• totalSize - the total size in the application's repository for items of this type
• sizePercentage - the size of this item type as a percentage of all the other item types in the application's repository

A common use of this information is to see what is contributing to the size of a repository database. For the EWM application, workitem attachments often take up a lot of the space. This bean will help track growth of those items typically taking up most space in the repository. Strategies then can be put in place to reduce their size, such as use of the attachment migration utility to remove orphaned attachments.

Further, tracking the number of artifacts in a repository for some applications is important given some applications have known size limits. For example, the Engineering Test Management (ETM) application has been tested with up to 15 million artifacts in v7.0.1. Tracking all the relevant item types that contribute to the overall ETM artifact count size, would be advisable to ensure you stay within the limit and track your growth towards it. This allows you to be proactive in managing growth and taking appropriate actions, such as deploying another application server.

Project Area Information MBean

Whereas the Item Count Details MBean provides data counts at the application repository level, the Project Area Information provides some details on the project areas of an application. There are several attributes of interest, but for purposes of tracking data counts relevant to sizing, consider the following (see the reference documentation for the full list).

• workitemCount - total number of workitems in an EWM project area
• attachmentCount - total number of workitem attachments in an EWM project area
• attachmentTotalLength - total size of workitem attachments in an EWM project area
• totalNoOfComponents - total number of components in a configuration management enabled project area
• totalNoOfStreams - total number of streams in a configuration management enabled project area
• totalNoOfBaselines - total number of baselines in a configuration management enabled project area
• rmArtifactCount - total number of artifacts in a configuration management enabled DOORS Next project area

There are no known limits for the different EWM data elements (work items, files, builds, etc.) in a project area, however you might find it useful to track which projects are most active and making use of workitems. Per the discussion on the Item Count Details MBean, tracking the size of attachments in a repository is important to help manage the overall EWM database size. Tracking attachmentTotalLength in the Project Area Information MBean allows you to see which projects are the primary contributors to attachment storage.

In 7.0 performance: IBM Engineering Requirements Management DOORS Next, there are recommended data limits for a project area, such as its total artifacts and components. These can be monitored with the totalNoOfComponents and rmArtifactCount attributes of this MBean.

Note that collecting data for the Item Count Details MBean can be resource intensive; care should be taken to when it is scheduled and how frequent.

DOORS Next MBeans

In 7.0, DOORS Next implemented several MBeans to aid in tracking various data shapes at the repository level. At a minimum, plan to monitor these DOORS Next MBeans:

• TotalNumberOfArtifacts - total artifacts in a DOORS Next application repository
• TotalNumberOfComponents - total components in a DOORS Next application repository
• TotalNumberOfBaselines - total baseline configurations in a DOORS Next application repository
• TotalNumberOfStreams - total stream configurations in a DOORS Next application repository
• TotalNumberOfLinks - total links within and between components and projects in a DOORS Next application repository

Each of these have their own Value attribute that publishes the count for the data item it is tracking. Of these TotalNumberOfArtifacts and TotalNumberOfComponents have published limits for 7.0.

Note that calculation of the values for these DOORS Next MBeans can add substantial load on large repositories; care should be taken to when it is scheduled and how frequent.

External links:

• How many artifacts do I have in my Jazz application repository?