Tuesday September 13, 2005

Dataspace Profiling Insight – Look Inside the Machine!

Gain Insight from Multiple Perspectives. Dataspace Profiling Insight dissects performance bottlenecks within the Perspective they are visible. Then, the bottleneck in its entirety can be observed from any other Perspective. The correlation between one Perspective to another offers Insight.

Let’s walk through an example of an Application with a scaling issue.

From the Perspective of L2 Cache, Dataspace Profiling observes:

Select the offending L2 Cache Line entry, and Filter to “Look Inside the Machine” just from the Perspective of this one L2 Cache Line.

To gain Insight, we observe the L2 Cache Line in its entirety from the Perspective of the Virtual Addresses used by the Application:

We gain the Insight, that just four neighboring Virtual Addresses incur the most cost to that one L2 Cache Line.

To gain more Insight, we observe these four Virtual Addresses when they occupy the L2 Cache Line in their entirety:

Now observed from the Perspective of the Processes used by the Application:

We have more Insight. One L2 Cache Line is used by many Processes of the Application and by just four neighboring Virtual Addresses.

We observe the Segment Profile and see the Virtual Memory Segment using 64k Sized Pages. More Insight!

One L2 Cache Line is used by:

• Many Processes of the Application;
• Four neighboring Virtual Addresses;
• One 64k-sized Page.

As I’ve shown you in my previous blog entry, you can have any Perspective you want.

With Dataspace Profiling, you gain Insight into your Application from the Program View and Hardware View. In the Program View, you gain Insight into the Functions, Threads, Type Definitions and Virtual Memory Allocations. In the Hardware View, you gain Insight into the Physical Memory Placement, the Cache Hierarchy Utilization, Memory Management Unit Utilization, Execution Unit Utilization, and even Time.

With Dataspace Profiling Insight, scaling issues are self-evident.

Dataspace Profiling – Look Inside the Machine!