5 ms·

The oldest parts are not System 360, they run IBM 7074 assembly. Just FYI. The caching system is much newer, they have some Java proxy, there were posts about i

by chx 9y ago

The oldest parts are not System 360, they run IBM 7074 assembly. Just FYI. The caching system is much newer, they have some Java proxy, there were posts about it the last year.

rbanffy 9y ago
I assume it runs under an emulator by now. Once I did manual disassembly of compiled code back into a high-level (for the time) language. It wasn't very fun, but , thankfully, the compilers of the day didn't optimize much. It'd be a fun project.
- DrScump 9y ago
  the compilers of the day didn't optimize much I worked in the IBM mainframe segment to start my career, and we actually had an awesome Capex optimizing COBOL compiler. We also had a core dump formatting system (not sure if it was part of the Capex set) that made dumps much easier to read and debug, plus they broke out the generated assembler code to make it quite intuitive. I got so good with reading their dumps that going to the first realtime debuggers was slower.
  - rbanffy 9y ago
    In this case, it was a C compiler for MS-DOS.
cptskippy 9y ago
> they run IBM 7074 assembly That potentially puts them in the late 50s. That might be some of the oldest running code in the world. That's pretty cool. I wonder if the person who wrote it is still alive?
- chx 9y ago
  https://archive.org/stream/irshistoricalfac00unit/irshistoricalfac00unit_djvu.txt https://archive.org/stream/irshistoricalfac00unit/irshistori... a bit broken up but it says clearly: > January 1962 Automated data processing was officially put into operation in the IRS. https://www.irs.gov/pub/irs-soi/62dbfullar.pdf https://www.irs.gov/pub/irs-soi/62dbfullar.pdf says > --Dn September 19, 1961, less than a year following its establishment as a separate division, the Automatic Data Processing Division... So the division was likely established in 1960. This https://books.google.ca/books?id=x1YESXanrgQC&pg=PA119&lpg=PA119&dq=Martinsburg+irs+mainframe&source=bl&ots=ZJ_Ald8sY2&sig=JnDB_-3VboxS0sLF3v0GQub_xKs&hl=en&sa=X&ved=0ahUKEwiS1p7V7-PaAhUM2GMKHfveAHc4ChDoAQg0MAQ#v=onepage&q=Martinsburg%20irs%20mainframe&f=false https://books.google.ca/books?id=x1YESXanrgQC&pg=PA119&lpg=P... history corroborates by saying the treasury authorized the IRS to computerize fully in 1959. They were 7074, we know that from http://blog.modernmechanix.com/big-brother-7074-is-watching-you/ http://blog.modernmechanix.com/big-brother-7074-is-watching-... Popular Science but also that some docs from 2016 says https://www.irs.gov/pub/irs-utl/scap-pia.pdf https://www.irs.gov/pub/irs-utl/scap-pia.pdf > SCAP downloads Corporate Files On-Line (CFOL) data from the IBM mainframe at the Enterprise Computing Center, Martinsburg. The CFOL data resides in a variety of formats (packed decimal, 7074, DB2, etc.). > That might be some of the oldest running code in the world. https://www-03.ibm.com/ibm/history/exhibits/dpd50/dpd50_chronology2.html https://www-03.ibm.com/ibm/history/exhibits/dpd50/dpd50_chro... says The IBM 9090 SABRE airline reservation system begins to be installed by American Airlines in 1961. That makes SABRE contemporaneous with the IRS Master Files or slightly older. I do not know, however, how much of that code is running today.
DonaldFisk 9y ago
The manual for the 7070, which was similar, is here: http://www.bitsavers.org/pdf/ibm/7070/A22-7003-01_7070_Reference_Jan60.pdf http://www.bitsavers.org/pdf/ibm/7070/A22-7003-01_7070_Refer... The instruction set documentation starts at page 42.
- chx 9y ago
  The manual... and it's less than 300 pages... oh boy, I remember the System 3090 manual, it was several metres thick :D (in several volumes, of course)

by chx 9y ago

The oldest parts are not System 360, they run IBM 7074 assembly. Just FYI. The caching system is much newer, they have some Java proxy, there were posts about it the last year.

rbanffy 9y ago

I assume it runs under an emulator by now. Once I did manual disassembly of compiled code back into a high-level (for the time) language. It wasn't very fun, but , thankfully, the compilers of the day didn't optimize much. It'd be a fun project.

DrScump 9y ago
the compilers of the day didn't optimize much I worked in the IBM mainframe segment to start my career, and we actually had an awesome Capex optimizing COBOL compiler. We also had a core dump formatting system (not sure if it was part of the Capex set) that made dumps much easier to read and debug, plus they broke out the generated assembler code to make it quite intuitive. I got so good with reading their dumps that going to the first realtime debuggers was slower.
- rbanffy 9y ago
  In this case, it was a C compiler for MS-DOS.

cptskippy 9y ago

> they run IBM 7074 assembly That potentially puts them in the late 50s. That might be some of the oldest running code in the world. That's pretty cool. I wonder if the person who wrote it is still alive?

chx 9y ago
https://archive.org/stream/irshistoricalfac00unit/irshistoricalfac00unit_djvu.txt https://archive.org/stream/irshistoricalfac00unit/irshistori... a bit broken up but it says clearly: > January 1962 Automated data processing was officially put into operation in the IRS. https://www.irs.gov/pub/irs-soi/62dbfullar.pdf https://www.irs.gov/pub/irs-soi/62dbfullar.pdf says > --Dn September 19, 1961, less than a year following its establishment as a separate division, the Automatic Data Processing Division... So the division was likely established in 1960. This https://books.google.ca/books?id=x1YESXanrgQC&pg=PA119&lpg=PA119&dq=Martinsburg+irs+mainframe&source=bl&ots=ZJ_Ald8sY2&sig=JnDB_-3VboxS0sLF3v0GQub_xKs&hl=en&sa=X&ved=0ahUKEwiS1p7V7-PaAhUM2GMKHfveAHc4ChDoAQg0MAQ#v=onepage&q=Martinsburg%20irs%20mainframe&f=false https://books.google.ca/books?id=x1YESXanrgQC&pg=PA119&lpg=P... history corroborates by saying the treasury authorized the IRS to computerize fully in 1959. They were 7074, we know that from http://blog.modernmechanix.com/big-brother-7074-is-watching-you/ http://blog.modernmechanix.com/big-brother-7074-is-watching-... Popular Science but also that some docs from 2016 says https://www.irs.gov/pub/irs-utl/scap-pia.pdf https://www.irs.gov/pub/irs-utl/scap-pia.pdf > SCAP downloads Corporate Files On-Line (CFOL) data from the IBM mainframe at the Enterprise Computing Center, Martinsburg. The CFOL data resides in a variety of formats (packed decimal, 7074, DB2, etc.). > That might be some of the oldest running code in the world. https://www-03.ibm.com/ibm/history/exhibits/dpd50/dpd50_chronology2.html https://www-03.ibm.com/ibm/history/exhibits/dpd50/dpd50_chro... says The IBM 9090 SABRE airline reservation system begins to be installed by American Airlines in 1961. That makes SABRE contemporaneous with the IRS Master Files or slightly older. I do not know, however, how much of that code is running today.

DonaldFisk 9y ago

The manual for the 7070, which was similar, is here: http://www.bitsavers.org/pdf/ibm/7070/A22-7003-01_7070_Reference_Jan60.pdf http://www.bitsavers.org/pdf/ibm/7070/A22-7003-01_7070_Refer... The instruction set documentation starts at page 42.

chx 9y ago
The manual... and it's less than 300 pages... oh boy, I remember the System 3090 manual, it was several metres thick :D (in several volumes, of course)