Ggate Professional sets GCOS connectivity performance records
Ggate is unique in many ways. It is available for Windows, Linux and UNIX servers and is scale-able over a wide range of server configurations.
Host Links R6.1 includes Ggate Professional Edition, a G&R gateway to Bull GCOS mainframes. The most interesting of Ggate's capabilities is its unbeatable performance in terms of the number of simultaneous sessions it can support, and the throughput it provides for those sessions.
This release extends the performance to new record levels. The performance is scalable, limited only by the processor power and available memory of the server. Additionally, and almost unbelievably, Ggate has proved that it can provide SSL encryption for the sessions with only a fraction of the expected loss in maximum number of sessions and throughput, bringing SSL encryption within the grasp of many customers at absolutely no cost in additional hardware.
Gallagher & Robertson's most widely known product is Glink, our terminal emulator for Bull, IBM and UNIX/Linux mainframes. Over 600.000 copies of Glink have been licensed worldwide.
Although widely used in IBM and UNIX/Linux environments, the largest and most closely concentrated clusters of Glink users are Bull GCOS customers, who can have several thousand users connecting to a single Bull mainframe for transaction processing. For this reason, early in the life of Glink, we developed our own gateway to the Bull GCOS systems. Our objectives for Ggate were clear:
Commodity TCP/IP between Glink and Ggate
Native Bull DSA from Ggate to the GCOS systems
An absolute minimum of processing in Ggate
An absolute minimum memory requirement in Ggate
Extension of fully functional Bull DSA session to Glink
The last feature is extremely important, since Glink is itself able to manage the many 'terminal handling' functions that are otherwise often implemented in a gateway or front-end. This minimalstic and clean design has made Ggate a worldwide winner in GCOS connectivity.
In R6.1 Ggate Professional brings you new performance records when connecting to Bull GCOS7 and GCOS8 systems. This performance is available and qualified for all Bull GCOS systems, including new GCOS7 Diane systems and new GCOS8 Olympus systems.
The performance results quoted here were achieved using a live GCOS8 Olympus mainframe. The test transactions were real, but 'null' transactions, i.e. the TP8 test TPR simply responded immediately.
Live testing on a UNIX server in 'extreme' conditions
The Ggate system was a Bull AIX 4-processor 4GB of memory.
The maximum number of simultaneous sessions through a single Ggate system on UNIX has been increased to 15.000.
With a zero think time, i.e. continuous transaction input, the maximum throughput was more than 2.600 transactions a second.
Using a 10 second think time, with 8.000 sessions the transaction rate was the theoretical maximum of 800 transactions a second, using 40% of the available CPU.
Using a 50 second think time, with 10.000 sessions, the transaction rate was the theoretical maximum of 200 transactions a second, using only 15% of the available CPU.
Live testing of a Windows server
The Ggate system was a Windows 2000 server with 2 800MHz processors and 2 GB of memory.
The maximum number of simultaneous sessions through a single Ggate system on Windows has been increased to 5.000.
Using a 10 second think time and 4.000 simultaneous sessions, the Windows server gave us the expected 400 transactions a second, using 40% of the available CPU.
Using a 50 seconds think time and 5.000 simultaneous sessions gave the expected 100 transactions per second, using ony 15% of the available CPU.
Live tests using Secure Socket Layer (SSL)
The encryption algorithms for SSL are processor intensive, particularly during the connection phase. The test results showed the the number of connections that could be established each second dropped, but that the 'steady state' number of simultaneous sessions and the throughput were not seriously affected, unless the server was already being used at maximum load. The following results show steady state throughput for SSL sessions, after all the sessions were established.
Using a think time of 50 seconds 10.000 SSL sessions gave us the expected 200 transactions a second, using ony 15% of the available processor.
Using a think time of 50 seconds 5.000 SSL sessions gave us the expected 100 transactions a second, using only 15% of the processor.
G&R/Ggate Professional gives Bull users an almost unlimited performance in connectivity, both for the number of simultaneous sessions, and for throughput. This applies to UNIX, Linux and Windows servers. Your choice of server platform, power and memory size is simply a function of the number of simultaneous sessions and the throughput you need.
It also gives many Bull users a unique possibility for moving to Secure Socket Layer for encryption and authentication of their terminal emulation clients, without investment in extra hardware.