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One hundred thirty gigabytes

Posted: Fri Jul 03, 2015 1:50 pm
by sje
One hundred thirty gigabytes is the approximate total amount of memory in use for transposition table storage by the Perft(14) project.

The twelve machine table:

Code: Select all

Machine  Log2(N)  Entries (= N)  Bytes            MiB
-------  -------  -------------  ---------------  -------
amanda        30  1,073,741,824   25,769,803,776   24,576
betty         25     33,554,432      805,306,368      768
cynthia       29    536,870,912   12,884,901,888   12,288
diane         31  2,147,483,648   51,539,607,552   49,152
gail          29    536,870,912   12,884,901,888   12,288
joni          28    268,435,456    6,442,450,944    6,144
kristen       29    536,870,912   12,884,901,888   12,288
megan         26     67,108,864    1,610,612,736    1,536
melissa       25     33,554,432      805,306,368      768
nancy         25     33,554,432      805,306,368      768
rocky         29    536,870,912   12,884,901,888   12,288
serra         25     33,554,432      805,306,368      768

Totals:           5,838,471,168  140,123,308,032  133,632  (= 130+ GiB)
If you are of a certain age, you might remember from some fifty years ago when a single byte of high speed memory built from discrete components cost US$1 in 2015 dollars.

Fifty years from now, how much memory will be in your computer?

Re: One hundred thirty gigabytes

Posted: Fri Jul 03, 2015 2:11 pm
by Joost Buijs
sje wrote: If you are of a certain age, you might remember from some fifty years ago when a single byte of high speed memory built from discrete components cost US$1 in 2015 dollars.

Fifty years from now, how much memory will be in your computer?
Maybe I'm not old enough, but I remember when I build my first computer that 16 KB of static RAM cost 1800 Dutch Guilders. That was the equivalent of about $0,04 for a single byte.

These RAM's were not very reliable, a few times a week I had one of these chips breaking down. After some time they became better. TI it was I believe.

Re: One hundred thirty gigabytes

Posted: Fri Jul 03, 2015 2:44 pm
by sje
I was a teenager when I built my first computer. The single 4 KiB RAM board kit cost about about US$2,000 in today's money, so each byte cost about US$0.05. But a few years earlier, before integrated circuit chips, the price for fast RAM was about a dollar a byte using discrete TTL latches and decoders.

The kit had 32 RAM chips, made by Intel and each had 1,024 bytes in a 1x1,024 bit array using ten bits of address decoding. The cycle time was about 450 ns.

Re: One hundred thirty gigabytes

Posted: Fri Jul 03, 2015 5:30 pm
by bob
sje wrote:One hundred thirty gigabytes is the approximate total amount of memory in use for transposition table storage by the Perft(14) project.

The twelve machine table:

Code: Select all

Machine  Log2(N)  Entries (= N)  Bytes            MiB
-------  -------  -------------  ---------------  -------
amanda        30  1,073,741,824   25,769,803,776   24,576
betty         25     33,554,432      805,306,368      768
cynthia       29    536,870,912   12,884,901,888   12,288
diane         31  2,147,483,648   51,539,607,552   49,152
gail          29    536,870,912   12,884,901,888   12,288
joni          28    268,435,456    6,442,450,944    6,144
kristen       29    536,870,912   12,884,901,888   12,288
megan         26     67,108,864    1,610,612,736    1,536
melissa       25     33,554,432      805,306,368      768
nancy         25     33,554,432      805,306,368      768
rocky         29    536,870,912   12,884,901,888   12,288
serra         25     33,554,432      805,306,368      768

Totals:           5,838,471,168  140,123,308,032  133,632  (= 130+ GiB)
If you are of a certain age, you might remember from some fifty years ago when a single byte of high speed memory built from discrete components cost US$1 in 2015 dollars.

Fifty years from now, how much memory will be in your computer?
When I graduated and was hired to run the computer operations at the University of Southern Mississippi, one of my first tasks was to buy 128K (yes K) bytes of memory for our IBM /360 model 40 (G40 to those that knew /360). Cost well over $100,000. I am currently testing on an Intel I7 box with 20 cores and 128gb of DRAM. Amazing capacity for someone that grew up thinking 128K to 512K was large memory. I remember running on a Cray-1 (serial # 12) that had 512K words of bi-polar ram (4mb) in 1980 when Blitz was ported to the Cray.

How much memory in 50 years? Who knows. Clearly not enough for Windows 50 years from now. :)

I assume the "kit" you mentioned was an Altair 8800? I built one of those as well. Along with the horrible cassette tape (via modem) interface.

Re: One hundred thirty gigabytes

Posted: Fri Jul 03, 2015 9:44 pm
by Joost Buijs
The kit I bought was a Heatkit H8 with a 16KB RAM board, 2 cassette decks and a H9 terminal.
I was working for Heatkit Netherlands at that time so I was one of the first to get this system.
Somewhat later I added 2 floppy drives and a hard disk to it, as I recall the floppy's were 180KB each and the hard disk was 5MB.
It was running HDOS, I think the precursor to MSDOS, very different from CP/M.

Re: One hundred thirty gigabytes

Posted: Sat Jul 04, 2015 2:48 am
by sje
My computer kit was an IMSAI 8080 with a single 4 KiB RAM board. I had much fun with the machine and I took it to college where I was the only student who had his own computer. I even used it in a demonstration lecture with the computer science faculty members for an audience.

But my budgeting skills weren't as good as my electronics assembly skills; paying for college expenses left no money for adding any peripherals to the computer. In all the time I owned it, I had only its front panel for communicating with the machine.

My second microcomputer was an Exidy Sorcerer, a Z80 machine with 16 KiB RAM and a couple of 8 KiB PROM modules, each housed in a 8-track tape cartridge. The assembled computer, made by a pinball machine company, also had an S-100 expansion box. I purchased this box, my idea being to use it to add a disk drive controller to free me from using cassette tape storage. But I never got any S-100 cards for it, because soon after I bought it, there were better, less expensive solutions from Radio Shack, Commodore, and Apple.

Re: One hundred thirty gigabytes

Posted: Sat Jul 04, 2015 2:59 am
by jdart
My first computer was also a Heathkit.

HDOS was written by Gordon Letwin. Despite being only one of the many operating systems that were born and died in that era, HDOS was fairly sophisticated: in particular I believe it was the first microcomputer OS to have device drivers that loaded at runtime from disk. Letwin later went to Microsoft and was Microsoft's lead architect for OS/2. He was indirectly an influence on later systems such as Windows NT.

I still remember when the IBM XT came out with a 10MB hard disk that cost $1000 (in 1982 or so dollars). Nowadays that is the size of one digital photo.

--Jon

Re: One hundred thirty gigabytes

Posted: Sat Jul 04, 2015 5:17 pm
by sje
My IMSAI 8080 was actually quite reliable other than its problem of edge connector contact oxidation. Every few weeks, I had to remove its cards and apply some gentle treatment to them with a pencil eraser.

After the IMSAI and the Sorcerer, I bought an overpriced US$4,000 8 MHz 8086 machine with a whopping 768 KiB RAM and a 10 MB drive. Its big problem was that it wasn't compatible with the IBM XT and its clones and so had to run a bastardized version of MS-DOS with little third party software available. But it did have a C compiler and so I didn't have to write chess programs in assembly language.

When the 8 MHz Mac Plus came out in 1986, I bought one so at last I could escape the idiot segmented memory model of the Intel 8086/80286 architecture. That machine, and other Motorola 68K Macs, kept me going for a long time in spite of none of them having hardware memory protection nor preemptive multiprocessing.

To experiment with Unix, along with the Mac Plus I got a generic Intel 33 MHz 486DX box which I loaded with MWC Coherent, a US$100 clone of early Unix. When Linux became available in the early 1990s, I switched over from Coherent; shortly after, the company which made Coherent went out of business as they couldn't compete with free Linux.

Re: One hundred thirty gigabytes

Posted: Sat Jul 04, 2015 9:02 pm
by Dirt
sje wrote:I was a teenager when I built my first computer. The single 4 KiB RAM board kit cost about about US$2,000 in today's money, so each byte cost about US$0.05.
Sounds more like US$0.50 to me.

Re: One hundred thirty gigabytes

Posted: Sun Jul 05, 2015 12:58 am
by sje
Dirt wrote:
sje wrote:I was a teenager when I built my first computer. The single 4 KiB RAM board kit cost about about US$2,000 in today's money, so each byte cost about US$0.05.
Sounds more like US$0.50 to me.
I've always had difficulty with arithmetic.