5 ms·
He means it is being compared to CPU cache (from the article), so there is tens of orders of magnitude difference. From this summary on stack overflow: http://
by amalag 15y ago
He means it is being compared to CPU cache (from the article), so there is tens of orders of magnitude difference. From this summary on stack overflow: http://stackoverflow.com/questions/433105/exactly-how-fast-are-modern-cpus http://stackoverflow.com/questions/433105/exactly-how-fast-a...
CPU registers (8-32 registers) – immediate access (0-1 clock cycles)
L1 CPU caches (32 KiB to 128 KiB) – fast access (3 clock cycles)
L2 CPU caches (128 KiB to 12 MiB) – slightly slower access (10 clock cycles)
Main physical memory (RAM) (256 MiB to 4 GiB) – slow access (100 clock cycles)
Disk (file system) (1 GiB to 1 TiB) – very slow (10,000,000 clock cycles)
Remote Memory (such as other computers or the Internet) (Practically unlimited) – speed varies
- pkulak 15y agoBut if you have a Redis cache on the same box (he says he only has one box anyway) it's still in the same category: "Main physical memory", with maybe some communication overheard.
- willvarfar 15y ago"maybe some communication overheard" is orders of magnitude slower than L1/L2. Hmm, there is something very wrong here. I'll try and explain in a blog post.
- pkulak 15y agoBut we're not talking register caches. 800 megs stashed in a giant Java hash are not going to be in L1 or L2 cache.
- willvarfar 15y agohttp://williamedwardscoder.tumblr.com/post/18065079081/cogs-bad#comment-446733732 http://williamedwardscoder.tumblr.com/post/18065079081/cogs-... might be interesting
- willvarfar 15y agohttp://williamedwardscoder.tumblr.com/post/18065079081/cogs-bad http://williamedwardscoder.tumblr.com/post/18065079081/cogs-...