Ask Slashdot: Is the Gap Between Data Access Speeds Widening Or Narrowing?

New submitter DidgetMaster writes: Everyone knows that CPU registers are much faster than level1, level2, and level3 caches. Likewise, those caches are much faster than RAM; and RAM in turn is much faster than disk (even SSD). But the past 30 years have seen tremendous improvements in data access speeds at all these levels. RAM today is much, much faster than RAM 10, 20, or 30 years ago. Disk accesses are also tremendously faster than previously as steady improvements in hard drive technology and the even more impressive gains in flash memory have occurred. Is the 'gap' between the fastest RAM and the fastest disks bigger or smaller now than the gap was 10 or 20 years ago? Are the gaps between all the various levels getting bigger or smaller? Anyone know of a definitive source that tracks these gaps over time?

Comments

What are you really asking?

[jeffb (2.718)]

I'm not sure what a historic timeline of these ratios (not "differences", please) would gain you.

These ratios can have a big impact on what algorithms and implementations you choose to maximize performance. I suppose if, say, the ratio of RAM to disk speed increased by a factor of 10 over the decade before last, then decreased back to its original ratio in the last decade, it might be worth trawling through some old papers (or old source trees) to revisit lessons learned in the earlier period -- but that seems like a bit of a stretch.

If you're just curious, it shouldn't be too hard to generate timelines of CPU cycle speeds, cache and RAM latencies and bandwidths, disk performance, and so on. But really, each of those has enough factors that a simple "ratio" would probably conceal more than it illuminates.

Writing a paper

[Anonymous Coward]

for a CS or IT class?