Issue 179: Tabbed Layout does not scale for >50 windows http://code.google.com/p/xmonad/issues/detail?id=179 Comment #3 by andrea.rossato: While I wonder how long it took to the xmonad algorithm complexity calculation team to lay out the math their O notated conclusions are based on (actually I'd really love to see that math too), still I'm sure the decoration module rewrite group formed within the xmonad developer team is going to take ages, literally, to reach an agreement with the tabbed module maintaining team on how to prototype a new decoration algorithm, given the constrains set out by the ACC team. Which is unfortunate for the casual xmonad user who needs to open 50-100 windows on the same workspace, quite typical for this kind of geek. Sadly I cannot be of any help. Still I was a bit amazed by the fact that iterating over such a short list of integers could lead to such a slow down - and even though I'm running a version of tabbed which has not been bloated with all the bottom, top, always, sometimes code, still I can reproduce your problem. So I decided to spend half an hour and did some math too. You know, not that scientifically sounded kind of proof a real haskeller would be able to do, but just some stupid old fashioned debugging, something even a LUA coder would be able to do: 1. I created a simple function to print out the time, with picoseconds (requires System.Time and System.IO): printNow :: String -> X () printNow s = do t <- io (toCalendarTime =<< getClockTime) io $ hPutStrLn stderr $ s ++ " - " ++ show (ctSec t) ++ "." ++ show (ctPicosec t) 2. Then I wrote a small layout modifier: data Debug a = Debug String deriving (Show, Read) instance LayoutModifier Debug Window where redoLayout (Debug s) _ _ wrs = do printNow s return (wrs, Nothing) 3. In .xmonad/xmonad.hs I wrote: main = xmonad defaultConfig {layoutHook = ModifiedLayout (Debug "tabbed") myTab } myTab = decoration shrinkText defaultTheme Tabbed (ModifiedLayout (Debug "Simplest") Simplest) I also called printNow at the very end of XMonad.Operations.windows. So we print the time: a. right after Simplest returned b. right after myTab returned c. at the end of the windows call. below there are the numbers of a few runs with enough tabs to slow everything down. I don't know if they are meaningful, this is why I'm posting them here. If they indeed are, then they are also a bit puzzling. If someone comes up with an idea on how to isolate the problem, please drop me a line. Historically I can say that from 0.4 up to 0.6 no changes have been made to tabbed and related code. The text size calculation code has been there from the very beginning of a tabbed layout (0.3 for sure) without changes. Anyway I think there's room for further investigation before calling for a rewrite (a tabbed layout with O(n) is something I'd really like to read, but I don't know if in that far future I'll still remember how to read Haskell). The numbers: Simplest - 57.187047000000 tabbed - 57.272167000000 Operations - 57.356136000000 Simplest - 57.356837000000 tabbed - 57.422710000000 Operations - 57.523055000000 Simplest - 57.523762000000 tabbed - 57.599250000000 Operations - 57.686736000000 Simplest - 59.65497000000 tabbed - 59.119980000000 Operations - 59.141826000000 Simplest - 1.672190000000 tabbed - 1.723279000000 Operations - 1.745065000000 Simplest - 3.152586000000 tabbed - 3.205879000000 Operations - 3.227333000000 Simplest - 5.839898000000 tabbed - 5.889285000000 Operations - 5.913992000000 Simplest - 5.914665000000 tabbed - 5.969013000000 Operations - 6.12130000000 Simplest - 6.12793000000 tabbed - 6.67688000000 Operations - 6.97815000000 Simplest - 6.98518000000 tabbed - 6.225578000000 Operations - 6.263437000000 Simplest - 6.264132000000 tabbed - 6.319227000000 Operations - 6.356627000000 Simplest - 6.357312000000 tabbed - 6.411805000000 Operations - 6.451679000000 Simplest - 7.712861000000 tabbed - 7.763174000000 Operations - 7.805636000000 Simplest - 7.806320000000 tabbed - 7.860956000000 Operations - 7.905911000000 Simplest - 7.906581000000 tabbed - 7.962566000000 Operations - 8.23426000000 if you want more you know how to do it. -- You received this message because you are listed in the owner or CC fields of this issue, or because you starred this issue. You may adjust your issue notification preferences at: http://code.google.com/hosting/settings