May 2014 - Pharo-dev - lists.pharo.org

Re: [Pharo-dev] String deduplication

by Chris Muller

I hope you're only considering this one-time for your Pharo release image, and not something that will _continue_ to operating on an on-going basis. Attempting to do that below app-layer would be way too intrusive for, for example, a Magma application.. A String read from one DB session belongs to that session. If it were canonicalized and suddenly belonged to two sessions, then mutating it would end up committing that change in both sessions. Bad. Strings aren't the only type to share. What about Dates? And literal-Array's? Timezones and Durations? This is an app-responsibility, not a system one. A one-time compress prior to release is okay, but not automatically behind the scenes.. On Fri, May 30, 2014 at 2:39 AM, Philippe Marschall <philippe.marschall(a)netcetera.ch> wrote: > Hi > > This is an idea I stole from somebody else. The assumption is that you have > a lot of Strings in the image that are equal. We could therefore remove the > duplicates and make all the objects refer to the same instance. > > However it's not a simple as that. The main issue is that String has two > responsibilities. The first is as an immutable value object. The second is > as a mutable character buffer for building immutable value objects. We must > not deduplicate the second kind. Unfortunately it's not straight forward to > figure out which kind a string is. The approach I took is looking at whether > it contains any 0 characters. An other option would be to check whether any > WirteStreams are referring to it. > Also, since there are behavioral differences between String and Symbol > besides #= we must exclude Symbols (eg. there is #'hello' and 'hello' in the > heap and they compare #= true but we must not make anybody who refers to > 'hello' suddenly refer to #'hello'). > > Anyway here's the code, this saves about 2 MB in a fairly stock Pharo 3 > image. Sorry for the bad variable names. > > | b d m | > b := Bag new. > d := OrderedCollection new. > m := Dictionary new. > "count all string instances" > String allSubInstancesDo: [ :s | > s isSymbol ifFalse: [ > b add: s ] ]. > "find the ones that have no duplicates or are likely buffers" > b doWithOccurrences: [ :s :i | > (i = 1 or: [ s anySatisfy: [ :c | c codePoint = 0 ] ]) ifTrue: [ > d add: s -> i ] ]. > "remove the ones that have no duplicates or are likely buffers" > d do: [ :a | > a value timesRepeat: [ > b remove: a key ] ]. > "map all duplicate strings to their duplicates" > String allSubInstancesDo: [ :s | > s isSymbol ifFalse: [ > (b includes: s) ifTrue: [ > | l | > l := m at: s ifAbsentPut: [ OrderedCollection new ]. > l add: s ] ]. > "remove the duplicates" > m keysAndValues do [ :k :v | > | f | > f := v at: 1. > 2 to: v size do: [ :i | > (v at: i) becomeForward: f ] ] > > Cheers > Philippe > >

May 30, 2014

Re: [Pharo-dev] OpenGL 3.0+

by Sean P. DeNigris

darrinm wrote > Oh, and NBMacGLConstants is lacking necessary constants. Is it manually > created or generated somehow? > > - darrinm ----- Cheers, Sean -- View this message in context: http://forum.world.st/OpenGL-3-0-tp4760914p4761009.html Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com.

May 30, 2014

Re: [Pharo-dev] OpenGL 3.0+

by Sean P. DeNigris

darrinm wrote > I'm trying to use #version 330 OpenGL shaders but NBOpenGL, on OSX anyway, > doesn't: > > 1. Specify the appropriate attributes (KCGLOGLPVersion_3_2_Core) when > requesting a gl context. > 2. Deal with other differences between OpenGL 3.0 and prior versions (e.g. > changes to querying extensions and built-in extensions). > > I can fix this but I'd like my to fix to be in line with Pharo plans for > OpenGL support. What are they? Continue to support older OpenGL versions? > Deprecate them somehow? > > - darrinm ----- Cheers, Sean -- View this message in context: http://forum.world.st/OpenGL-3-0-tp4760914p4761008.html Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com.

May 30, 2014

Re: [Pharo-dev] GPU accelerated GUI

by Sean P. DeNigris

darrinm wrote > On my Mac, Pharo's UI performance (e.g. window dragging, scrolling, any > kind of animation) is quite a bit less than the rest of the system. I > expect high frame rates for such basic things. It impacts everything I do > and makes me sad. > > I'm still learning and would like to know: > > 1) Is this also the case on Linux and Windows? > 2) I'm reading that Pharo's GUI is not hardware accelerated. Is this the > primary issue with UI performance? > 3) If so, is work to incorporate hardware acceleration in progress? > 4) If so, how can I help?! > > - darrinm ----- Cheers, Sean -- View this message in context: http://forum.world.st/GPU-accelerated-GUI-tp4760898p4761007.html Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com.

May 30, 2014

Re: [Pharo-dev] Recover lost changes doesn't recover classes created.

by Stephan Eggermont

https://pharo.fogbugz.com/default.asp?13290#103226

May 30, 2014

Recover lost changes doesn't recover classes created.

by Stephan Eggermont

Recover lost changes doesn't recover classes created. Mac Mavericks Open 30848 image Create a package AA Create a class AAA in it Create a method aaaa in it, setting the author Create a subclass of AA BB Quit without saving. Restart image, try to recover

May 30, 2014

Re: [Pharo-dev] Change list background color in Pharo with Spec

by Nicolai Hess

2014-05-30 14:24 GMT+02:00 Esteban Lorenzano <estebanlm(a)gmail.com>: > > http://stackoverflow.com/questions/23944704/change-list-background-color-in… > > > How about this: ListModel new items: (1 to: 10); backgroundColorBlock: [ :item :index |Color red ]; openWithSpec. (I am not registered at stackoverlfow, please forward).

May 30, 2014

Re: [Pharo-dev] String deduplication

by Nicolas Cellier

I'm curious to see which method is really using mutable strings. Of course, while constructing and write streaming on it, but then it's like a temporary storage area and we don't have to care. We're speaking of a place where a String would be modified to retain some state... Of course, since we can't exclude this possibility theoretically, the proposed changed is unsafe. But practically... 2014-05-30 13:46 GMT+02:00 Marcus Denker <marcus.denker(a)inria.fr>: > > On 30 May 2014, at 10:59, ClÃ©ment Bera <bera.clement(a)gmail.com> wrote: > > Hello, > > I like the idea but this is not as simple. > > In some framework you may use different string with a same name as markers > that are not equals. > > Typically: > > Object>>#string1 > ^ 'string' > > Object>>#string2 > ^ 'string' > > Object>>#test > self assert: self string1 == self string1. "Answers true" > self assert: self string2 == self string2. "Answers true" > self assert: self string1 == self string2 "Answers false" > > Frameworks relying on that will not work any more. > > And this kind of bugs is not easy to spot, it typically crashes identity > collections in a non deterministic fashion. > > > With an indirection (a kind of reference) that > > -> points to the string > -> forwards everything, but does a copy on write on state change > -> implements == to return false > > > it would work. Of course you have then the same amount of objects(+1), but > they would be all very > small, thus leading to saving for large objects and especially when > applied to subgraphs. > > Marcus > > > Regards > > > 2014-05-30 9:39 GMT+02:00 Philippe Marschall < > philippe.marschall(a)netcetera.ch>: > >> Hi >> >> This is an idea I stole from somebody else. The assumption is that you >> have a lot of Strings in the image that are equal. We could therefore >> remove the duplicates and make all the objects refer to the same instance. >> >> However it's not a simple as that. The main issue is that String has two >> responsibilities. The first is as an immutable value object. The second is >> as a mutable character buffer for building immutable value objects. We must >> not deduplicate the second kind. Unfortunately it's not straight forward to >> figure out which kind a string is. The approach I took is looking at >> whether it contains any 0 characters. An other option would be to check >> whether any WirteStreams are referring to it. >> Also, since there are behavioral differences between String and Symbol >> besides #= we must exclude Symbols (eg. there is #'hello' and 'hello' in >> the heap and they compare #= true but we must not make anybody who refers >> to 'hello' suddenly refer to #'hello'). >> >> Anyway here's the code, this saves about 2 MB in a fairly stock Pharo 3 >> image. Sorry for the bad variable names. >> >> | b d m | >> b := Bag new. >> d := OrderedCollection new. >> m := Dictionary new. >> "count all string instances" >> String allSubInstancesDo: [ :s | >> s isSymbol ifFalse: [ >> b add: s ] ]. >> "find the ones that have no duplicates or are likely buffers" >> b doWithOccurrences: [ :s :i | >> (i = 1 or: [ s anySatisfy: [ :c | c codePoint = 0 ] ]) ifTrue: [ >> d add: s -> i ] ]. >> "remove the ones that have no duplicates or are likely buffers" >> d do: [ :a | >> a value timesRepeat: [ >> b remove: a key ] ]. >> "map all duplicate strings to their duplicates" >> String allSubInstancesDo: [ :s | >> s isSymbol ifFalse: [ >> (b includes: s) ifTrue: [ >> | l | >> l := m at: s ifAbsentPut: [ OrderedCollection new ]. >> l add: s ] ]. >> "remove the duplicates" >> m keysAndValues do [ :k :v | >> | f | >> f := v at: 1. >> 2 to: v size do: [ :i | >> (v at: i) becomeForward: f ] ] >> >> Cheers >> Philippe >> >> >> > >

May 30, 2014

Change list background color in Pharo with Spec

by Esteban Lorenzano

http://stackoverflow.com/questions/23944704/change-list-background-color-in…

May 30, 2014

Re: [Pharo-dev] String deduplication

by Marcus Denker

On 30 May 2014, at 10:59, ClÃ©ment Bera <bera.clement(a)gmail.com> wrote: > Hello, > > I like the idea but this is not as simple. > > In some framework you may use different string with a same name as markers that are not equals. > > Typically: > > Object>>#string1 > ^ 'string' > > Object>>#string2 > ^ 'string' > > Object>>#test > self assert: self string1 == self string1. "Answers true" > self assert: self string2 == self string2. "Answers true" > self assert: self string1 == self string2 "Answers false" > > Frameworks relying on that will not work any more. > > And this kind of bugs is not easy to spot, it typically crashes identity collections in a non deterministic fashion. > With an indirection (a kind of reference) that -> points to the string -> forwards everything, but does a copy on write on state change -> implements == to return false it would work. Of course you have then the same amount of objects(+1), but they would be all very small, thus leading to saving for large objects and especially when applied to subgraphs. Marcus > Regards > > > 2014-05-30 9:39 GMT+02:00 Philippe Marschall <philippe.marschall(a)netcetera.ch>: > Hi > > This is an idea I stole from somebody else. The assumption is that you have a lot of Strings in the image that are equal. We could therefore remove the duplicates and make all the objects refer to the same instance. > > However it's not a simple as that. The main issue is that String has two responsibilities. The first is as an immutable value object. The second is as a mutable character buffer for building immutable value objects. We must not deduplicate the second kind. Unfortunately it's not straight forward to figure out which kind a string is. The approach I took is looking at whether it contains any 0 characters. An other option would be to check whether any WirteStreams are referring to it. > Also, since there are behavioral differences between String and Symbol besides #= we must exclude Symbols (eg. there is #'hello' and 'hello' in the heap and they compare #= true but we must not make anybody who refers to 'hello' suddenly refer to #'hello'). > > Anyway here's the code, this saves about 2 MB in a fairly stock Pharo 3 image. Sorry for the bad variable names. > > | b d m | > b := Bag new. > d := OrderedCollection new. > m := Dictionary new. > "count all string instances" > String allSubInstancesDo: [ :s | > s isSymbol ifFalse: [ > b add: s ] ]. > "find the ones that have no duplicates or are likely buffers" > b doWithOccurrences: [ :s :i | > (i = 1 or: [ s anySatisfy: [ :c | c codePoint = 0 ] ]) ifTrue: [ > d add: s -> i ] ]. > "remove the ones that have no duplicates or are likely buffers" > d do: [ :a | > a value timesRepeat: [ > b remove: a key ] ]. > "map all duplicate strings to their duplicates" > String allSubInstancesDo: [ :s | > s isSymbol ifFalse: [ > (b includes: s) ifTrue: [ > | l | > l := m at: s ifAbsentPut: [ OrderedCollection new ]. > l add: s ] ]. > "remove the duplicates" > m keysAndValues do [ :k :v | > | f | > f := v at: 1. > 2 to: v size do: [ :i | > (v at: i) becomeForward: f ] ] > > Cheers > Philippe > > >

May 30, 2014