SAS Grid Manager Modernization: Do You Have a Plan?

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Organizations benefitting from SAS Grid Manager in their SAS 9 environments, who are eager to modernize their projects, can now move to SAS Workload Management on SAS Viya.

As organizations move their analytic and data management workloads to the cloud, they are faced with challenges in balancing cost and agility. Is it possible to balance good performance with acceptable cloud infrastructure costs? A simple lift and shift of legacy software, not specifically designed for the cloud, may seem simpler to implement than a more comprehensive redesign. In the long term, however, that decision may result in an environment that is not optimized.

What does a grid modernization plan look like? What are the key factors to consider?

Grid Modernization, Layer by Layer

Within the Global Enablement and Learning team, we’ve been teaching SAS Grid Manager architecture, deployment, and administration to hundreds of professionals for more than a decade.

In the latest version of our workshops, we present this slide in the introductory modules:

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This slide shows a simple, high-level view. We briefly explain the “filling inside the sandwich” as follows:

SAS Infrastructure: This is the SAS 9 Platform, including the SAS Metadata Server, SAS Middle Tier components, etc.
Grid Infrastructure: Also called grid middleware, includes specialized software that sits between computing processes and the underlying Operating System.

Is this relevant while discussing a modernization plan? It is, because modernizing a SAS 9 grid environment to SAS Workload Management on SAS Viya requires that you consider all the elements in the picture above and know how each one maps in the new world.

Most of the activities that you will perform use migration procedures from SAS 9 to SAS Viya described in the Full-System Migration and Content Migration documentation – the same that you would perform in environments that do not include SAS Grid Manager or SAS Workload Management.

Let’s discuss each layer of the sandwich in more detail, from the bottom up.

Provision a cloud-hosted Kubernetes environment to replace the current hardware and operating system components of the current SAS 9 environment
- This may range from using the SAS Viya Infrastructure as Code (IaC) projects to provision a cloud environment similar to your existing SAS 9 one, to a complete architecture redesign.
- See the SAS Global Forum 2020 paper “Important Performance Considerations When Moving SAS® to a Public Cloud” by Margaret Crevar.
- No grid-specific considerations - except, when required, the design of high-performance cloud storage. This may be a surprise for architects used to design SAS 9 environments. When SAS Grid Manager is included with SAS 9, you have specific architecture considerations, i.e. in terms of distributed storage. But remember, every SAS Viya environment in Kubernetes is, by default, distributed on multiple nodes. SAS Workload Management does not change that.
Modernize the SAS platform from SAS 9 to SAS Viya
- This step includes deploying and configuring SAS Viya in the infrastructure prepared in the previous step.
- See the SAS Viya: Deployment Guide
- Grid specific considerations: be familiar with SAS Workload Management deployment; for example, the requirement to assign the workload.sas.com=compute label to compute nodes. You can read more in the article SAS Workload Management on SAS Viya: Deployment Architecture.
Move the grid environment configuration
- This point covers migrating the grid itself.
- Re-design the grid configuration: queues, host types, grid administrators, daemon tuning, etc. See SAS Viya: Workload Management.
- If you are already leveraging SAS Grid Manager, with SAS Workload Orchestrator as your grid provider, you will recognize that most grid configuration settings are the same between the two environments.
- For SAS Grid Manager for Platform, after moving from SAS 9 to SAS Viya, you will use SAS Workload Orchestrator instead of IBM Spectrum LSF, and SAS Job Flow Scheduler instead of Platform Process Manager.
- Currently, there are no tools to automatically export the existing grid configuration from SAS 9 into SAS Workload Orchestrator on SAS Viya. You will have to manually re-create the grid configuration. Work is being evaluated to provide such tools to analyze the source environment and, eventually, migrate the configuration to the new target.
- In any case, perform an assessment of the existing environment. Business objectives may have changed, grid usage patterns evolved, and some configuration items may not make sense anymore in the new Kubernetes cloud environment. You may reach the conclusion that it may be better to re-design the grid configuration.
Migrate the software clients that use the grid, including content and programs that run on the grid
- Be familiar with "standard" SAS 9 to SAS Viya modernization considerations. Examples include:
  - how to migrate from SAS Enterprise Guide or SAS Data Integration Studio to SAS Studio
  - for grid batch submission, switch from the sasgsub cli to the sas-viya batch cli.
- To simplify code, report, and content analysis, SAS provides the SAS 9 Content Assessment, a collection of applications designed to examine the characteristics of your existing SAS 9 system.
- Work is underway to add features to allow scheduled flows to be exported from SAS 9 and imported into SAS Job Flow Scheduler on SAS Viya.
- No other grid-specific considerations - unless the code contains explicit SAS grid syntax which may need to be evaluated, removed, or re-written. Examples include explicit references to grid nodes or the grdsvc_enable statement.

For an in-depth review on how to approach a grid modernization project, see the SAS Global Forum 2021 paper “Stretch Your Mind and Your SAS® Grid” by Diane Hatcher. It was written before the SAS Workload Management release and only addressed SAS Grid Manager on SAS 9 “uplifting” to cloud environments, but it still contains a lot of useful suggestions on how to structure and plan your digital transformation to the cloud.

Modernize Grid Capabilities

A complementary approach in designing your modernization plan is to look at SAS Grid Manager functionalities that bring value to your business, and how they map into the new world.

SAS Grid Manager provides a rich set of capabilities including workload management (through queueing and job prioritization), central administration, high availability, parallel processing, scalability, and simplified, non-disruptive, maintenance.

While it’s clear that SAS has brought SAS Grid Manager functionality to SAS Viya, it may not be so obvious what are the modernization paths. SAS Workload Management brings the core capabilities of SAS Grid Manager - workload management, parallel processing, and central administration - to the SAS Viya platform by extending the core scheduling capabilities of the underlying Kubernetes infrastructure. Other capabilities, such as scalability, elasticity, high availability, and non-disruptive maintenance, leverage Kubernetes' native features. SAS Workload Management is integrated into the Viya platform including integration with SAS Studio, SAS Compute, SAS Batch, SAS/CONNECT, and Job Flow Scheduler.

In summary, some of the grid functionality is inherent in SAS Viya’s Kubernetes architecture. Other features are provided by SAS Workload Management which is layered on top of SAS Viya. To get a more comprehensive review, capability by capability, see the article SAS Grid and SAS Viya: together to provide advanced workload management. Also be on the lookout, in the coming months, for additional grid and migration related articles provided by GEL.

Conclusion

Modernizing a SAS 9 grid environment to SAS Workload Management on SAS Viya does not require complex procedures, but does require proper planning. At the end of the journey, you will be able to leverage new capabilities not available before, such as dynamic scaling up to accommodate increased workloads, and down to control cloud costs.

Find more articles from SAS Global Enablement and Learning here.