4 ms·

3) Profile before optimization.

by sethrin 8y ago

AstralStorm 8y ago
4) After thinking how to get beat bang for buck when optimizing. Profilers don't always pinpoint the culprit.
- kungtotte 8y ago
  I have a hard time seeing how profilers don't at least point you in the right direction. Or are we using different definitions of the word? They tell you how much time is spent in any given section of your program. If 80% of the time is spent in 20% of the code, it's usually a safe bet that's where you should start looking!
  - sethrin 8y ago
    Profilers have limitations like anything else, and it's possible to be pointing the flashlight in the wrong place. I probably wouldn't include that as a list item. By the by, is there more than one kungtotte on the Internet? It took me a minute to think why that name was so familiar, but then I remembered watching a few hundred Beaglerush videos.
    - kungtotte 8y ago
      There must be more than one, because I've never heard of Beaglerush. I've used this handle for a long time though (20 years or so), so it's all over the internet.
      - sethrin 8y ago
        Kk, thank you for indulging my curiosity. Beaglerush is a very humorous Aussie who is notable for a video series on the Long War mod for the game XCOM. Long War turns a moderately challenging game of thirty or forty hours into an extremely complex, impossibly difficult ordeal of at least 400 hours per game. Beagle apparently often uses the handles of his friends as character names, and one of the best/worst parts of XCOM is that it's really good at making you care about the little blobs of pixels you order into virtual mortal peril, so to me kungtotte is like, the hero of 100 missions :) If you're into strategy games, XCOM is good, and Long War is matchless. However, Beaglerush is actually surprisingly entertaining even if you don't care for his subject; the girlfriend is still not much into the game, but after the first couple episodes she insisted on watching the other hundred-thirty-odd videos. It's probably not everyone's cuppa, but it could be a thing.
        kungtotte 8y ago
        Oh, that's me then :) I didn't put two and two together because I knew him as just beagle, and it was a long time ago that I hung out with him. We played together in a gaming community known as ShackTac or ShackTactical, playing a game called Armed Assault/ArmA. Way back when a bunch of us put our names into a custom name file for XCOM so people could make campaigns featuring ShackTac people instead of generic dudes. I completely forgot about that until you reminded me. It must be five years since I talked to him :)
        sethrin 8y ago
        Oh cool :) Yeah, I did get the impression that the name list represented more former acquaintances than current ones, and I think he got pretty burnt out on YouTube generally. He seemed like a pretty great guy, and the series was excellent, so it seems you have a small measure of reflected glory at least :)
  - taneq 8y ago
    Generally I agree, but after you've picked off a few low hanging fruit, you'll end up with the profiler pointing at the function which does most of your grunt work, at which point you'd expect that to take up most of the time. Once you've got this pretty optimized and it's still taking up the lion's share of your execution time, you have to look elsewhere (probably changing your overall approach or applying some higher level optimisation) to improve things further.
    - AstralStorm 8y ago
      Yes, at that point you typically get to apply far reaching architectural changes or switch out the algorithm. Sometimes it is quicker to start with just that instead of "polishing a turd". You can get it to be shiny but still nowhere near as shiny as gold. Hope the code is testable and reasonably easy to modify. Otherwise it's going to be a rewrite. The profile is then useful as a benchmark on real data. If you have enough time, you can turn that into a high level performance test.

3) Profile before optimization.

AstralStorm 8y ago

4) After thinking how to get beat bang for buck when optimizing. Profilers don't always pinpoint the culprit.

kungtotte 8y ago
I have a hard time seeing how profilers don't at least point you in the right direction. Or are we using different definitions of the word? They tell you how much time is spent in any given section of your program. If 80% of the time is spent in 20% of the code, it's usually a safe bet that's where you should start looking!
- sethrin 8y ago
  Profilers have limitations like anything else, and it's possible to be pointing the flashlight in the wrong place. I probably wouldn't include that as a list item. By the by, is there more than one kungtotte on the Internet? It took me a minute to think why that name was so familiar, but then I remembered watching a few hundred Beaglerush videos.
  - kungtotte 8y ago
    There must be more than one, because I've never heard of Beaglerush. I've used this handle for a long time though (20 years or so), so it's all over the internet.
    - sethrin 8y ago
      Kk, thank you for indulging my curiosity. Beaglerush is a very humorous Aussie who is notable for a video series on the Long War mod for the game XCOM. Long War turns a moderately challenging game of thirty or forty hours into an extremely complex, impossibly difficult ordeal of at least 400 hours per game. Beagle apparently often uses the handles of his friends as character names, and one of the best/worst parts of XCOM is that it's really good at making you care about the little blobs of pixels you order into virtual mortal peril, so to me kungtotte is like, the hero of 100 missions :) If you're into strategy games, XCOM is good, and Long War is matchless. However, Beaglerush is actually surprisingly entertaining even if you don't care for his subject; the girlfriend is still not much into the game, but after the first couple episodes she insisted on watching the other hundred-thirty-odd videos. It's probably not everyone's cuppa, but it could be a thing.
      - kungtotte 8y ago
        Oh, that's me then :) I didn't put two and two together because I knew him as just beagle, and it was a long time ago that I hung out with him. We played together in a gaming community known as ShackTac or ShackTactical, playing a game called Armed Assault/ArmA. Way back when a bunch of us put our names into a custom name file for XCOM so people could make campaigns featuring ShackTac people instead of generic dudes. I completely forgot about that until you reminded me. It must be five years since I talked to him :)
        sethrin 8y ago
        Oh cool :) Yeah, I did get the impression that the name list represented more former acquaintances than current ones, and I think he got pretty burnt out on YouTube generally. He seemed like a pretty great guy, and the series was excellent, so it seems you have a small measure of reflected glory at least :)
- taneq 8y ago
  Generally I agree, but after you've picked off a few low hanging fruit, you'll end up with the profiler pointing at the function which does most of your grunt work, at which point you'd expect that to take up most of the time. Once you've got this pretty optimized and it's still taking up the lion's share of your execution time, you have to look elsewhere (probably changing your overall approach or applying some higher level optimisation) to improve things further.
  - AstralStorm 8y ago
    Yes, at that point you typically get to apply far reaching architectural changes or switch out the algorithm. Sometimes it is quicker to start with just that instead of "polishing a turd". You can get it to be shiny but still nowhere near as shiny as gold. Hope the code is testable and reasonably easy to modify. Otherwise it's going to be a rewrite. The profile is then useful as a benchmark on real data. If you have enough time, you can turn that into a high level performance test.