dvyukov · HackerTrans

I do not see anything about memory fences. If Jinx does not support them, then it's pretty much useless for verification of synchronization algorithms. I've implemented dozens of advanced synchronization algorithms, and I may say that it's crucial. Also, if it works on binary level (does not require re-compilation), then it also renders it useless, because on that level you lose information about order of memory accesses, memory fences, atomicity. For example, if you see plain x86 MOV instruction, what is it? non-atomic store? atomic relaxed store? atomic release store?

dvyukov

16 anni fadiscuss

It's "similar" to a lot of software out there: Intel Thread Checker, Chord, Zing, Spin, RacerX, CheckFence, Sober, Coverity Thread Analyzer, CHESS, KISS, PreFast, Prefix, FxCop. However, what you are missing is that most of these tools (and Jinx as far as I see, can't find clear description on the site, mostly vague marketing stuff) are of help to you if you are an application developer who writes in term of mutexes. While RRD is of help to you if you are implementing mutexes itself. Can you verify involved mutex algorithm down to possible memory access reorderings? I doubt.

> and is most likely much faster. Or an order of magnitude slower.

dvyukov

16 anni fadiscuss

I am very close to covering a first year of hosting :) As for consulting and, perhaps, paid libraries, well, first I need a good site, right?

dvyukov

16 anni fadiscuss

The intention was actually something like "atomic-RMW-free", that is "costly-operation-free". It should also include expensive memory fences, and excessive sharing. I have an explanation of "atomic-free" in the Russian article, but I did not transfer it to the English page on xxx-free. Sorry for any confusion. I think I better just remove it from the main page for now.

dvyukov

16 anni fadiscuss

> Scaling today means running on more than one machine

Of course it's not. Hundreds of millions of people use just a single computer for a lot of tasks.

>you might as well drastically simplify your code by writing it "single-threaded" and running #cores copies on each machine.

It's not the worst approach. However there may be significant penalties in terms of performance and latency in some contexts. You are definitely don't want to use your approach for games and browsers. As for server software it depends on performance/latency requirements. For example, if you will use it in High-Frequency Trading marker, count you loose all your money.

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