Indeed.... There are some physical limits that are imposed by design on these 64-bit designs (128 - 1024GB?), but you are absolutely correct the virtual addressing capabilities would be theoretically 2^64 which is just ridiculous!
To give folks an idea of how big 18 exabytes is, if you started DLing an 18 exabyte "file" at 3 megabits/second (decent broadband cable speed), it would take about 1,558,778 years. Assuming no down time, of course. A million and a half years, LOL.
yeah i'm not too sure. All i know is that my trading manager told me that recording and scalping caused at least a half second -2 second delay in order execution...and since this is all about being a order routing monkey and being quicker, recording and scalping for a penny were off limits according to him... but then i thought...well...what if i maxed out the ramm and used a processor designed for multitasking... what do you guys think? I want the recording to play back like it was in real time...not some crummy powerpoint presentation where the mouse is lagging.
I don't record, but I do a screenshot, and sometimes print charts. I know that NihabaAshi occasionally records his trades, you might PM him for some ideas. Take a look at the file size of your recordings. Are they megabytes or gigabytes? Meg, I bet. If you only have files that are a hundred meg (or less) a gig of RAM should be fine. And that's gonna have more to do with the playback application, and possibly your disk speed. But if you are playing a 100 meg file with a 1024 meg of RAM, then your app should queue it all up.
i just meant i want the recording to look decent when i do it. On 1 mhz processor with only 256 mb of ramm, recording the background is pretty bad.
32 bit processor can address upto 4GB... get 4GB ram while it is cheap get an AMD 64bit processor, the limit is almost endless... (for now)
Hi newguy1, I do live-recordings of my trading every day. Sometimes these live-recordings of several monitors with audio can produce +500mg files very easily. Pentium M or AMD 64 Athlon is suitable for such (I don't know anything about Pentium D). I say that because I have the above because I have Pentiim M and AMD 64 among my systems. Your going to need at least a minimum of 1 gig in memory to prevent in performance problems in your software that's doing the live-recordings... More importantly to prevent any problems in your trading applications while doing live-recordings. Now...if your going to be doing some serious editing of those live-recordings for whatever reasons for presentation use (macromedia applications)... Your going to need more than 1 gig of memory. P.S. I'm not a computer expert...so I'm the last one you want to talk about why some computer part is better than another computer part. NihabaAshi
Pentium D can probably use more than 4 GBytes of RAM . What do you need ? Depends upon your needs ... On Windows machines the performance counters can not only show you in real time the vairous system metrics but can also log them over a time period for later analysis. If you are getting upwards of 80% continuous usage on a critical parameter then you need to consider more capacity. On Linux you might need more or less memory to achieve a comparable process on Windows - depends upon the function. So, without an analysis you are just shooting blindfolded ..... On the other hand RAM is so cheap these days - as is storage - that you might as well just load up - few people actually need a GByte of Ram and fewer still need more than this or need multi-processor machines. Just buy and install a GByte - probably more than you will ever need.
Going back to the original question, according to my understanding, it's actually the L2 cache that sets the useable ram limit. In earlier years, with external cache, adding memory could dramatically slow the computer. With the L2 cache on the processor, as with the pentium 4, the ram limit is around 4 gb, which is as much as the chipsets will allow anyway. Some processors, such as the xeon, will far exceed the chipset possibilities. So your friend is correct, though as others are saying, it's not usually very important to trading applications.