Looking for “What New in Netweaver 7.4” I found some data about this topic that i wated to post it here.
An SAP system is dual-stack, if it contains both SAP NetWeaver Application Server ABAP and Java with one common SAP system ID (SAPSID), one common startup framework, and one common database. Support for dual-stack implementations for SAP NetWeaver was originally introduced with the intention to
reduce the TCO and to offer more options for the layout of SAP systems to customers deploying and running SAP NetWeaver-based products and solutions such as the SAP Business Suite. Initially, dual-stack allowed customers to save database and application server hardware and software deployments, by combining the
ABAP and Java stack on the same physical machine, sharing database and operating system resources. Software lifecycle management processes in turn treated ABAP and Java stack as a unit when applying support packages, installing enhancement packages, or upgrading the system.
Dual-stack implications and disadvantages
While the benefits and advantages of dual-stack implementations offered value and helped to reduce and manage the operational costs for certain use cases and aspects, many of the offered benefits were only one-time benefits (such as reduced efforts for implementation) and could also be achieved with single stack systems by other means, such as running both the ABAP and the Java schema of two single stack systems in the same database with Multiple Components in One Database (MCOD). Also, new technologies such as virtualization have been introduced in recent years that offer similar capabilities on a more appropriate level of abstraction.
In addition, the tight coupling between the ABAP and Java stacks became more and more an innovation hurdle, since the stacks evolved at different speeds and served different use cases moving forward. The ABAP stack continued to serve as a foundation platform for SAP’s solutions, such as the SAP Business Suite, while the Java stack was optimized to serve integration and collaboration capabilities. Since the downtime of one stack in a dual-stack system affected the whole system and since dual-stack systems could not be scaled independently, single-stack systems overall offered more advantages and improved flexibility.
Support for Dual-Stack discontinued in SAP NetWeaver 7.4 in general with exceptions
SAP NetWeaver 7.4 is positioned as the follow-up on-premise release for SAP NetWeaver 7.31.
SAP NetWeaver is among other things optimized for SAP HANA as the foundation for the SAP Business Suite on SAP HANA project. This means that dual-stack deployments and implementations are not supported any longer. The only exception to this rule is SAP NetWeaver Process Integration on a traditional database system, which still requires a dual-stack implementation. However, note that a single-stack SAP NetWeaver Process Integration Java exists that offers 95% of the features of classical dual-stack implementations. Therefore, customers should investigate whether an existing SAP NetWeaver PI implementation can be replaced by a Java-only implementation of SAP NetWeaver PI.
SAP NetWeaver Process Integration
In general, SAP NetWeaver PI dual-stack will be supported in SAP NetWeaver 7.4. However, customers are recommended to migrate SAP NetWeaver PI content into SAP NetWeaver PI Java single stack (Advanced Adapter Engine Extended). Since the feature set of the Advanced Adapter Engine Extended covers 95% of a classical SAP NetWeaver PI dual-stack environment, this approach should be feasible for most use cases. Due to the harmonized process orchestration stack (SAP NetWeaver PI and SAP NetWeaver BPM running on the same Java instance), many of the ccBPM features in SAP NetWeaver PI can be expressed using SAP NetWeaver BPM capabilities instead.
from PI 7.31 SP07 SAP release a wizard that allow user to migrate dual-stack scenarios to standalone (AAE) – refer to this BLOG
for more information abput What new in 7.4 take allok to this link
Hope it document lets you have a clear sight about the future of the tool.