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30% in overall execution time? Does your code consist mostly of enumerations and while loops?
No, it doesn't go from 90 to 60, unless all your code is enumerate. Real world code is more than just retrieving a list. Sorry Honey.
VS shows you the place where it spends most time. "Limited knowledge trans...", aight, you're allowed to your views, I have mine.
And yes, mucking about a for loop vs enumerable in an VB6 runtime (which .NET IS) is not even a microoptimization, it is purely whining. Write in a goddamn real language if it is that important an link to it from .NET where you need it.
You have fallen, my angel, and very deep. Time critical stuff isn't worth .NET, and it isn't worth my time to read about 20 ms savings in a different loop that is less readable.
When the situation calls for it, you want someone who works with pointers, not with .NET. I would write a library for you to link to that does the heavy lifting, "if the situation calls for it". Because .NET is just an evolution of VB6, it is just a runtime interpreting with a memory manager. It is vbruntime600 with additional libraries. Any compiled language with pointers laughs out loud.
This is not even an argument honey.
EVERYONE can use a profiler and see how much your micro optimization may help them. If it does, then yay for them for writing ineffcient code.
My code does not consist of merely enumerations, it deals with a lot more stuff. Real world code consist of more than "looping".
And if speed is that paramount then why are you using .NET? Are you really blabbing about how to do a for loop in a VB-variant? That is what C# is, VB6 in a new interface, but that translates 1 on 1 to VB. You really whining about the performance of BASIC code (by any other syntax, but still a rose/VB)?
And you prove it by throwing some unreadable code, that saves me 20 ms? That is going to impress, really. You will shave of some ms, sacrificing readability for some code that takes more than 2 secs? Did you know that humans only see 48 frames per second? The END USER will not even notice, but the manager that pays someone to update your code WILL.
You're gonna go far kid.
Bastard Programmer from Hell
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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> 30% in overall execution time? Does your code consist mostly of enumerations and while loops?
In this case yes, in fact I posted the code, which is a regex matching algorithm.
> And yes, mucking about a for loop vs enumerable in an VB6 runtime (which .NET IS) is not even a microoptimization, it is purely whining. Write in a goddamn real language if it is that important an link to it from .NET where you need it.
I wasn't whining. I was making an observation. You're looking for a fight. I have better things to do with my time. Grow up.
Also VB.NET and VB6 runtimes have nothing to do with each other. You don't even know what you're talking about. Funny how arrogance and ignorance go hand in hand so often.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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A fringe case, as most of us do not write regex-libs, and anyone who would doesn't use an interpreter but a compiler. No, not a byte code compiler, that's just a fancy marketing sh*t for an interpreter that doesn't compile to native.
And yes, I'm looking for a fight; you are implying that some loop in an interpreter is interesting. It isn't.
VB.NET and VB6 are ridiculously the same. I've done that discussion a thousand times, where a manager imagined C# to be superior to VB.NET. It is a different syntax for the same VBRUN300.DLL, a fakkin interpreter that does bytecode like VB6 did with the same memory manager.
C# is marketing, but under the hood it is just VB7 with a different style of writing. Which is brilliant from an MS perspective btw, which proves MS is still the best.
Now, get off my lawn.
Bastard Programmer from Hell
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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Linq makes it not a fringe case since it uses enumerations all over the place.
It's also a known documented issue with .NET. I'm far from the first person to make this observation. Folks from Microsoft have said as much.
And yes, you're looking for a fight. I'm an adult, which is why I was looking for a discussion. You're clearly not capable of something like that so we're done.
Feel free to keep running your mouth about .NET, in case anyone wasn't already convinced that you don't know half of what you're on about.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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Quote: Linq makes it not a fringe case since it uses enumerations all over the place. You disliked Linq? Normal code doesn't require Linq? Did you make this microoptimization to prove you're better than Linq?
Quote: It's also a known documented issue with .NET. I'm far from the first person to make this observation. Folks from Microsoft have said as much. Is that the basis of your post? Maybe you missed the point; 20 ms is nothing in a background thread, and I would remove your code from any codebase for being unreadable and obfuscating. I gladly pay a few ms for readability, maintenance and fewer bugs. That is implying that there's only .NET devs and that there's no person available who can write in a language that compiles to native. You call those things "libraries".
Quote: And yes, you're looking for a fight. I'm an adult, which is why I was looking for a discussion. You're clearly not capable of something like that so we're done. So, that is your defense? You little twat copied MS and you can't handle me saying it ain't so?
Thank you for the limitless list of arguments and examples.
Wait, there's none?
"Folks from MS have said".. and you copied and try to impress. Sorry, but you didn't with your 20 ms. As if all code is a regex-lookup, which you present as if your micro optimization invalidates every foreach. If you want to regex, use a native language. I will BREAK your nonsense.
I do not care about you copying MS and presenting it as "your" observation. I just puke over the generalization
Bastard Programmer from Hell
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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You seriously called me a "twat"?
What the hell is wrong with you? You are a child. You can't even code in C or C++, and you talk about Delphi like that's a flex. It's a joke. You're a joke, and you're a belligerent clown. I've reported your account because this isn't the first time you've been abusive and hostile to other people.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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Quote: I've reported your account because this isn't the first time you've been abusive and hostile to other people. I cannot argue that, as it is true. I do not have much patience.
Quote: You are a child You meant "childish".
Bastard Programmer from Hell
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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I would have been happy to debate this with you.
That changed when it became clear to me that weren't interested in actually debating anyone.
You came here for a fight. You came here because you wanted to abuse other people.
You have some issues, and you are making them the problem of other people here.
That's not cool.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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Not taking sides, but your posts are so much like the arguments I used to hear from my fellow Navy nucs. I kind of miss it, but we Navy nucs re an odd lot.
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"and anyone who would doesn't use an interpreter but a compiler. No, not a byte code compiler, that's just a fancy marketing sh*t for an interpreter that doesn't compile to native."
Far as my limited experience goes C#, Java and JavaScript use an interpreter for their regexes.
And I know Perl does.
I suspect JavaScript like Perl cannot be anything but an interpreter (in most usages.)
At least for Java it might at some point go Native. Same could be true of C#.
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Any other day, this would go. Today is not that day.
It isn't 30% even if all you do is enumerate.
GC's is losing performance by definition of what the beast is made of. Show me one example of .NET that outperforms Delphi? Where, o where, would an interpreter with a lot of libraries outperform a compiled native language?
You .NET dev? Than you write in VB7, complete with a GC and a runtime interpreter. Your code will be faster than anything I write in a real compiler, innit? And your 20 ms on 60 is gonna make a 30% if it is only enumerating, because all that code does is enumerate.
I am not even amused a bit. Obfuscation to save a few ms. Yeah, that will help, really. You saved the world, but the rest of us are going to use enumerations because it is a damned good tradeof for those that only know .NET and cannot handle pointers. It makes code readable, which yours damned ain't. Great, you reduced some code by 20 ms. Most code takes longer.
Was there anything else you'd like to whine about, or are we done?
BPFH
Bastard Programmer from Hell
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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I love GC for jobs that allocate 14 Gigs of memory and then finish.
Poof!
14 gigs of memory returned to the OS very quickly. No need to clean the heap.
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I mean, if you have it, why not, with a modern damned paged vmem system and gobs of RAM on a modern machine? Spare your program having to garbage collect as often.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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honey the codewitch wrote: Spare your program having to garbage collect as often. So you prefer to collect tons of garbage before doing anything about it? Then you may have some job to do when space runs out ...
Nothing wrong to be said about having 'enough' RAM, but if there is anything risk at all of having to garbage collect (and if you use heap allocation at all, there is ), I would much prefer to do it in small steps!
If you have got plenty of RAM, I'd much rather close my ears to all the whining about the internal fragmentation of buddy allocation (the only serious argument against buddy that I have encountered), to have a very fast allocation / deallocation mechanism, that also lends itself to incremental garbage collection.
Religious freedom is the freedom to say that two plus two make five.
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It depends on what I'm doing. In some scenarios, such as when you don't need to garbage collect but for at the end, such as CLI tools often do then yes, absolutely, because you've finished doing useful work and you don't need to make the user wait for the collection (even if the process is still running at that point you can have written out all of your output and everything.)
I write a lot of command line tools that do complicated things, like Deslang: From Code to CodeDOM and Back[^] that absolutely benefit from doing things this way.
I should add, that modern GCs collect in the background, and that should perhaps influence one's decision as it's probably less expensive overall to do one large collection than a bunch of little ones, particularly when asynchronicity is involved.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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If you do buddy with a set of freelist heads, one for each size, and your buddy combiner orders the freelist, you have an extra benefit of locality: most accesses would go to the lower end of the heap, making better use of virtual memory (less paging).
A background GC could unhook a freelist (maybe leaving a couple entries in the list for use while the GC was working), returning with one shorter list for the original freelist and one list of combined buddies to be put into the next higher size freelist.
The head end of the freelist may be rather unordered - this is where all the allocation and freeing is taking place. If the list is long - it hasn't been emptied for quite some time - the tail end may be perfectly sorted after the previous GC/combination round. If you do sorting e.g. by Smoothsort, handling the already sorted part has complexity O(n), so most likely, the long freelist will not required much effort.
You find buddies by traversing a sorted list, so the list of buddy pairs will also be sorted. If the next higher freelist is also mostly sorted, all buddy pairs is inserted into this is list in a single traversal.
I would do real timing tests with a synthetic heap load (modeled after a relevant usage scenario) to see if it really is worthwhile the resource cost of an asynchronous GC thread - strongly suspecting that a finely tuned incremental but synchronous buddy manager can do it both at a lower total resource cost and with so small delays that it would be a much better solution.
Final remark:
"you've finished doing useful work and you don't need to make the user wait for the collection". In most systems, each process has its own heap. Multiple processes allocating from one common global heap requires a lot of resource consuming synchronization. Most CLI programs are run in their own processes. So when they complete, noone cares about what their heap looks like at that time. There is no reason to do any garbage collection at that time. The entire data segment holding the heap is released en bloc.
In an embedded system, you often have a single systemwide heap. But few embedded system have CLI interfaces for running arbitrary programs that start up and terminate as a function of user operations. Even if the embedded system has some sort of UI, user actions are usually limited to activating specific built-in operations in the embedded code, not separate CLI oriented programs. But of course, there may be exceptions
Religious freedom is the freedom to say that two plus two make five.
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Welcome to my bandwagon. I've been saying this for ages. Don't use foreach unless you have to -- or where it doesn't matter.
Having said that... I hypothesize that foreach has improved. To test this hypothesis, last summer (?) I was testing and measuring some comparisons and I didn't see much difference. I was unable to form conclusions at that time because I wasn't convinced that the tests were valid.
I'll have another look later.
P.S.
And besides, you mean iteration, not enumeration -- I blame Microsoft for misnaming the thing.
modified 19-Jan-24 11:05am.
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I've said it before, but this is one of the few times I've used it in a critical codepath.
PS: I'm using enumeration because we're talking about .NET. If I started talking about iterators in .NET parlance that's a C# compiler feature.
Iterators and iterating are terms I'd use if we were talking about C++. You may not agree with my terminology but I tend to choose it with some deliberation.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
modified 18-Jan-24 21:50pm.
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You "think"?
We do not think, we measure. If you say that you think, you think that you think.
Measure or shut the elephant op.
Bastard Programmer from Hell
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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Of course it's slower. The IEnumerable interface expects a class with methods you have to call to maintain which item in the IEnumerable implementor you're looking at.
Calling methods adds overhead, and plenty of it compared to the overhead of an index variable, which you know is just pointer math.
Enumerable being slower is not surprising at all. Just don't use it where you don't have to, and that includes LINQ because it's heavily dependent on the IEnumerable interfaces.
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IList<t> uses methods as well. Virtual calls and everything. There is no direct array access through IList<t> afaik
So the primary difference between IEnumerable<t> and IList<t> is the creation of a new object to traverse the former.
Microsoft appears to believe that object creation is very cheap in .NET, and everything I've read from them suggests they practically think it's free. It's not.
That was 30% gain in performance.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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Well, the first call (GetEnumerator) definitely has a penalty, but each retrieval after that (each call to the enumerator) may be as quick as an indexed access... or it may not be.
Anyway, I agree with -- if you know you're iterating across an array, use array access instead.
And don't use Linq.
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Just to be difficult, I'd argue that an Enumerator - even a special cased one like the implementation on System.String will be slower than indexed access.
The reason being is that it's necessary to execute an additional call to MoveNext() for each advance, whereas with indexed access you are simply incrementing a value. You must then call Current to get the actual value.
I haven't benchmarked it, but I'd be very surprised if this was not the case.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
And my IoT UI/User Experience library here:
https://honeythecodewitch.com/uix
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