Bass said:Dexter said:*snip*
Ha ha, look who's talking. You're twisting my words yet you claim "losing argument".
Well I see you want to be on an equal footing with me on this. So I'll call you an insane person also. Insane person.
And how exactly does this relate to what I said? Or more generally, how exactly does this relate to caching?
This is the original point I am addressing:
Seriously, do you really want/expect a database system to move gigabytes or terrabytes of data around just to keep the kernel happy?
Okay I'm going to say this again. Please no more "NUH UHs" on this. I'm quite obviously right.
You can not write any explicit caching code to efficently cache things on an x86 processor. This algorithm is hardcoded into the control unit of the actual processor. The only way to get important data into cache (which is of course, what you want) is to "suggest" it to the proccessor by your data structures. This means working with the quirks of the branch predictor, and also localizing commonly accessed data.
Of course this is to keep the CPU happy and you are probably going to be like "well I didn't say CPU, so I am somehow correct, and you are wrong". Well buddy, you have to keep the CPU happy. A unhappy CPU is a cache missing CPU, and you MUST avoid this to have any reasonable performance.
And interestingly, by keeping the CPU happy, you also tend to make the kernel happy. Because the kernel isn't using some magical caching algorithm that Intel doesn't know about.
See --- this long post by Bass right here.
This is why I want Channel 9 forums to switch to something with a little bit more maturity like SMF or phpBB or something. The delays in bringing up posts, the times when you can't get to page 2 of a thread, and the over-AJAXification of the current Channel 9 forums interrupts and distracts from a steady stream of posts like this one which are both highly entertaining, yet educational.
If I had succumbed to the urge to just not visit the site a few minute ago (an urge fueled mainly by the usability of these forums), I would not have read this post.