System / 370
System / 370 (also S / 370 ) was a mainframe architecture from IBM .
The System / 370 was an evolutionary further development of the System / 360 and was announced by IBM in the summer of 1970. System / 370 was followed by System / 390 , which was further developed into the current System z mainframe architecture.
The most important innovation was the dynamic address translation . In addition to the OS / 360 of the S / 360, the first operating systems with virtualization OS / VS1 VM / 370 , OS / VS2 SVS, OS / VS2 MVS and DOS / VS could be used as operating systems .
Magnetic tapes and hard disks were used as storage media, the most common initially being the removable hard disk type 3330 with approx. 100 MB, then the type 3350 with 317 MB and finally the type 3380 with approx. 600 MB (models A, B, D, E and J) up to 1.8 GB (model K). From 1974 the IBM 3850 mass storage subsystem was also supported.
Models
The purchase price of a Model 165 with 1 MB main memory amounted to 4,674,160 US dollars , for maintenance and service 12,450 US dollars were payable monthly. Alternatively, monthly rent was offered at $ 98,715. Including peripheral devices such as magnetic disk drives or printers, the monthly rent could, however, be significantly higher. In Germany in 1974 a joint venture around the Sparkasse Trier paid 150,000 DM per month for an IBM 370/145 including peripheral devices. Although the hardware from a single source was more expensive than the competition, the "higher operational reliability" was decisive for the network - a fact that the company IBM knew how to use.
| model | year | processing unit | random access memory |
|---|---|---|---|
| Model 155 | 1970 | IBM 3155 |
256 - 2048 Kbytes
|
| Model 165 | 1970 | IBM 3165 |
512 - 3072 Kbytes
|
| Model 145 | 1970 | IBM 3145 |
160 - 2048 Kbytes
|
| Model 135 | 1971 | IBM 3135 |
96 - 512 Kbytes
|
| Model 195 | 1970 | IBM 3195 |
1024 - 4096 Kbytes
|
| Model 158 | 1972 | IBM 3158 |
512 - 6144 Kbytes
|
| Model 168 | 1972 | IBM 3168 |
1024 - 8192 Kbytes
|
| Model 125 | 1972 | IBM 3125 |
96 - 256 Kbytes
|
| Model 115 | 1973 | IBM 3115 |
64 - 192 Kbytes
|
| Model 115-2 | 1975 |
64 - 384 Kbytes
|
|
| Model 125-2 | 1975 |
96 - 512 Kbytes
|
|
| Model 158-3 | 1976 | IBM 3158-3 |
512 - 6144 Kbytes
|
| Model 168-3 | 1976 | IBM 3168-3 |
1024 - 8192 Kbytes
|
| Model 135-3 | 1976 | IBM 3135-3 |
256 - 512 Kbytes
|
| Model 145-3 | 1976 | IBM 3145-3 |
192 - 1984 Kbytes
|
| Model 138 | 1976 | IBM 3138 |
512 - 1024 Kbytes
|
| Model 148 | 1976 | IBM 3148 |
1024 - 2048 Kbytes
|
| Model 158-AP | 1976 | Attached processor |
512 - 6144 Kbytes
|
Clones
In the Eastern Bloc , mainframe computers were developed under the name ESER in three series of computer systems. Series II ESERs were largely compatible with the IBM System / 370. The EC 1055, EC 1055M, EC 1056 and EC 1057 systems with central units from the VEB Kombinat Robotron were still in use in the GDR until the 1990s .