From: Hari K. <hk...@ti...> - 2014-02-17 18:24:16
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Hi Dr. Erez, Thank you. Appreciate the response. Cheers Hari. On Mon, Feb 17, 2014 at 1:45 AM, Erez Petrank <er...@cs...>wrote: > Hari, > > The use of a return barrier to allow concurrent stack scanning has > appeared in our VEE'09 paper. It may be useful to look at it. > > *Gabriel Kliot, Erez Petrank, and Bjarne Steensgaard. A Lock-Free, > Concurrent, and Incremental Stack Scanning for Garbage Collectors > <http://www.cs.technion.ac.il/~erez/Papers/sctack-scan-vee09.pdf>. Proceedings > of the 2009 ACM SIGPLAN/SIGOPS International Conference on Virtual > Execution Environments (VEE'09) <http://www.cs.purdue.edu/VEE09/Home.html>, > March 2009. * > > --Erez > > On Feb 14, 2014, at 5:48 AM, Hari Krishnan <hk...@ti...> wrote: > > Hi all, > I am implementing a Reference Counting based garbage collector. This > reference count implementation is concurrent as well as parallel capable of > collecting cycles efficiently. Every-time an object is pointed by any stack > root, I have to increment a separate counter in the object. This reference > count implementation is mainly based on stack roots. So every object has > a separate counter that counts the path from stack roots. So when any > object get the stack root, I have to increment it and so when ever any > object loses the support of stack roots I have to reduce that count. The > whole algorithm uses the stack roots as the fundamental idea. I could use > scanning of the stack in the collector part to identify the roots and > increment it. But that complicates our algorithm and have to change > algorithm to use deferred version of the algorithm which may or may not > impact the correctness of the algorithm (Although I started working out the > deferred version after realizing the features I wanted in Jikes RVM are too > hard to implement by myself and consumes lot of time). So I needed return > barrier to decrement the count of the object pointed by stack frame that is > about to be popped and identify when an objects gains the stack root. I > hope this clarifies my necessities. > > > On Thu, Feb 13, 2014 at 8:45 PM, Eliot Moss <mo...@cs...> wrote: > >> On 2/13/2014 2:57 PM, Hari Krishnan wrote: >> >> > 1. I want to know how to activate the return barriers and let the >> mutators know that a activation >> > record is about to be popped from the stack. >> >> Return barriers are a comparatively new addition, so I am afraid I >> personally >> can't help you about them -- but I'm sure someone else can! >> >> > 2. How can I find if an object is pointed by stack root at the time of >> assignment? >> >> You can't. Such assignments can get optimized in various ways that place >> the >> item into registers, etc. You have to get by with occasional scanning of >> frames or similar measures. >> >> Perhaps if you told us more about the particular kind of collector and >> your >> goals we could be of more assistance. There's a lot of knowledge here, >> but >> to tap into it you often have tell us the bigger picture. >> >> Regards -- Eliot Moss >> >> >> ------------------------------------------------------------------------------ >> Android apps run on BlackBerry 10 >> Introducing the new BlackBerry 10.2.1 Runtime for Android apps. >> Now with support for Jelly Bean, Bluetooth, Mapview and more. >> Get your Android app in front of a whole new audience. Start now. >> >> http://pubads.g.doubleclick.net/gampad/clk?id=124407151&iu=/4140/ostg.clktrk >> _______________________________________________ >> Jikesrvm-researchers mailing list >> Jik...@li... >> https://lists.sourceforge.net/lists/listinfo/jikesrvm-researchers >> > > > ------------------------------------------------------------------------------ > Android apps run on BlackBerry 10 > Introducing the new BlackBerry 10.2.1 Runtime for Android apps. > Now with support for Jelly Bean, Bluetooth, Mapview and more. > Get your Android app in front of a whole new audience. Start now. > > http://pubads.g.doubleclick.net/gampad/clk?id=124407151&iu=/4140/ostg.clktrk_______________________________________________ > Jikesrvm-researchers mailing list > Jik...@li... > https://lists.sourceforge.net/lists/listinfo/jikesrvm-researchers > > > |