5 ms·

Show HN: std::vector for c, upto 1/3 faster

4 points by tsegratis 8y ago

tsegratis 8y ago
I've made it as usable/tested/documented as I can over a couple of years Under 'how/detail/THANKS': explains internals; graphs optimizations; chat about my life Any feedback would be awesome ;)
gus_massa 8y ago
It would be nice to see the benchmark that support the 1/3 faster claim. I don't doubt it, but there are always a lot of hidden assumptions and details that are missing, that I'd like to see the exact benchmark. Is it a small vector? Is it a large vector? What happens for different vectors sizes? What about int vs a complex struct? Too many questions ... I'd would be better to change the license to an standard license. In the spirit of the current license I recommend looking at the BSD license without atribution. Try to search the different variants and pick the one that is closer to your wishes. It's funny to make up a license, but does your license protect you of liabilities if a moron uses your software badly? What about if your library has a bug? Also, someone inside a company may prefer a usual license because the company lawyers had review the usual license, but an unusual license needs too many talk with the lawyers to get approved.
- deleted 8y ago
  [deleted]
- tsegratis 8y ago
  Graphs are here: https://tse.gratis/aArray/#details https://tse.gratis/aArray/#details And you're completely right, benchmarking is hard Edit: To expand on that: I use someone else's benchmark since they have put effort into it, and already received feedback For std::vector and binary search I performed multiple runs on several architectures, and did things like randomizing the benchmark order (which can have a big impact) Complex struct is a good question
  - gus_massa 8y ago
    Add a link to it in the main page next to the 1/3 faster claim, something like "see the details". (Moreover, I'd add the graph in the overview page with a link to the complete discussion. I like graphs :) .)
    - tsegratis 8y ago
      Thankyou for your questions. They made me go back and re-test Saving vectors between runs and comparing their contents, changes things -- to the much more believable result of aArray being slower Only comparing the array lengths, but not their contents probably let gcc optimize out assignmemnts for aArray, but not std::vector -- leading to an unfair test Interestingly yes, std::vector now wins by a larger margin for int8_t arrays, and int64_t becomes a tighter match ----- Note: I've updated the website to remove the 1/3 claim! But I can no-longer edit the title of this thread The remaining stool legs of aArray are safety, simplicity, and being generic -- hopefully they don't get kicked out from under it quite so quickly ;^)
- tsegratis 8y ago
  Yeah, I'm having fun with the license I didn't want press any downstream user with adding another BSD/MIT/CC-0/license or copyright notice to their code base So the idea is that aArray is public domain and cc-0 and BSD and MIT and gpl and whatever you want -- simply delete the current license text and replace it with your own ----- In general I'm not sure where I stand. For instance python's source contains several: * Redistributions of source code/binary must retain the above copyright notice, this list of conditions and the following disclaimer... So if an app uses python then must it reproduce what is quite a long list of licenses?? Nobody does, but code from those licenses are still present

4 points by tsegratis 8y ago

I've made it as usable/tested/documented as I can over a couple of years Under 'how/detail/THANKS': explains internals; graphs optimizations; chat about my life Any feedback would be awesome ;)

gus_massa 8y ago

It would be nice to see the benchmark that support the 1/3 faster claim. I don't doubt it, but there are always a lot of hidden assumptions and details that are missing, that I'd like to see the exact benchmark. Is it a small vector? Is it a large vector? What happens for different vectors sizes? What about int vs a complex struct? Too many questions ... I'd would be better to change the license to an standard license. In the spirit of the current license I recommend looking at the BSD license without atribution. Try to search the different variants and pick the one that is closer to your wishes. It's funny to make up a license, but does your license protect you of liabilities if a moron uses your software badly? What about if your library has a bug? Also, someone inside a company may prefer a usual license because the company lawyers had review the usual license, but an unusual license needs too many talk with the lawyers to get approved.

deleted 8y ago
[deleted]
tsegratis 8y ago
Graphs are here: https://tse.gratis/aArray/#details https://tse.gratis/aArray/#details And you're completely right, benchmarking is hard Edit: To expand on that: I use someone else's benchmark since they have put effort into it, and already received feedback For std::vector and binary search I performed multiple runs on several architectures, and did things like randomizing the benchmark order (which can have a big impact) Complex struct is a good question
- gus_massa 8y ago
  Add a link to it in the main page next to the 1/3 faster claim, something like "see the details". (Moreover, I'd add the graph in the overview page with a link to the complete discussion. I like graphs :) .)
  - tsegratis 8y ago
    Thankyou for your questions. They made me go back and re-test Saving vectors between runs and comparing their contents, changes things -- to the much more believable result of aArray being slower Only comparing the array lengths, but not their contents probably let gcc optimize out assignmemnts for aArray, but not std::vector -- leading to an unfair test Interestingly yes, std::vector now wins by a larger margin for int8_t arrays, and int64_t becomes a tighter match ----- Note: I've updated the website to remove the 1/3 claim! But I can no-longer edit the title of this thread The remaining stool legs of aArray are safety, simplicity, and being generic -- hopefully they don't get kicked out from under it quite so quickly ;^)
tsegratis 8y ago
Yeah, I'm having fun with the license I didn't want press any downstream user with adding another BSD/MIT/CC-0/license or copyright notice to their code base So the idea is that aArray is public domain and cc-0 and BSD and MIT and gpl and whatever you want -- simply delete the current license text and replace it with your own ----- In general I'm not sure where I stand. For instance python's source contains several: * Redistributions of source code/binary must retain the above copyright notice, this list of conditions and the following disclaimer... So if an app uses python then must it reproduce what is quite a long list of licenses?? Nobody does, but code from those licenses are still present