digitalmars.D - Question about GC
- Tomás Rossi (3/3) Oct 24 2005 Is there a way to turn off the GC (Garbage Collector) in D?
- Walter Bright (4/6) Oct 24 2005 Sure. www.digitalmars.com/d/phobos/std_gc.html
- Tomás Rossi (7/13) Oct 27 2005 When disabling GC (std.gc.disable()) I just inhibit the GC cycles but, w...
- Sean Kelly (7/25) Oct 27 2005 D has some behind the scenes extern(C) callbacks for when new and delete...
- James Dunne (7/34) Oct 27 2005 I wrote a phobos patch way back in the long-long ago that's probably
- Tomás Rossi (12/46) Oct 27 2005 So, I'm tied to use GC if I want to take advantage of any of the Phobos
- Dave (23/71) Oct 27 2005 Well, as stated before, with D you can use malloc/free as much as you wa...
- Tomás Rossi (23/100) Oct 28 2005 Do you mean that not allowing you to allocate your objects in the stack ...
- Dave (13/117) Oct 29 2005 Well, that's part of it - just about everything has to be allocated on t...
- Tomás Rossi (4/135) Oct 29 2005 So, if I explicitly delete my objects most of the times, that would be a...
- clayasaurus (3/7) Oct 27 2005 GC is not as much as a bottleneck as you might think. Write some memory
Is there a way to turn off the GC (Garbage Collector) in D? What if I want to manage all the memory by myself? Is this possible? Tom
Oct 24 2005
"Tomás Rossi" <Tomás_member pathlink.com> wrote in message news:djj8qd$1ain$1 digitaldaemon.com...Is there a way to turn off the GC (Garbage Collector) in D?Sure. www.digitalmars.com/d/phobos/std_gc.htmlWhat if I want to manage all the memory by myself? Is this possible?Yes. You can even use C's malloc/free. See www.digitalmars.com/d/memory.html
Oct 24 2005
In article <djjic8$1ipg$2 digitaldaemon.com>, Walter Bright says..."Tomás Rossi" <Tomás_member pathlink.com> wrote in message news:djj8qd$1ain$1 digitaldaemon.com...When disabling GC (std.gc.disable()) I just inhibit the GC cycles but, what if I refuse to use the GC at all? what if I DON´T WANT the GC to be compiled with my program and still wan´t to use new & delete operators, just like C++? (some kind of conditional GC), can I do that? Sorry for my ignorance, I'm already loving this language though... TomIs there a way to turn off the GC (Garbage Collector) in D?Sure. www.digitalmars.com/d/phobos/std_gc.htmlWhat if I want to manage all the memory by myself? Is this possible?Yes. You can even use C's malloc/free. See www.digitalmars.com/d/memory.html
Oct 27 2005
Sean Kelly <sean f4.ca> In article <djqf6b$1p11$1 digitaldaemon.com>, Tomás Rossi says...In article <djjic8$1ipg$2 digitaldaemon.com>, Walter Bright says...D has some behind the scenes extern(C) callbacks for when new and delete are called, arrays are manipulated, etc--see phobos/internal/gc/gc.d for the bulk of them. If don't want the default GC to be compiled with your program then you will need to suppy stub implementations for these functions. It may be enough to simply call malloc/realloc/free as appropriate. Sean"Tomás Rossi" <Tomás_member pathlink.com> wrote in message news:djj8qd$1ain$1 digitaldaemon.com...When disabling GC (std.gc.disable()) I just inhibit the GC cycles but, what if I refuse to use the GC at all? what if I DON´T WANT the GC to be compiled with my program and still wan´t to use new & delete operators, just like C++? (some kind of conditional GC), can I do that?Is there a way to turn off the GC (Garbage Collector) in D?Sure. www.digitalmars.com/d/phobos/std_gc.htmlWhat if I want to manage all the memory by myself? Is this possible?Yes. You can even use C's malloc/free. See www.digitalmars.com/d/memory.html
Oct 27 2005
Tomás Rossi wrote:In article <djjic8$1ipg$2 digitaldaemon.com>, Walter Bright says...I wrote a phobos patch way back in the long-long ago that's probably outdated now... but it is theoretically a very simple patch. It simply ripped out the GC implementation and used C's malloc and free; naively I might add. Most of phobos is coded with use of the GC in mind, and is quite memory-leaky without it. All the GC related code is in src/phobos/internal/gc/."Tomás Rossi" <Tomás_member pathlink.com> wrote in message news:djj8qd$1ain$1 digitaldaemon.com...When disabling GC (std.gc.disable()) I just inhibit the GC cycles but, what if I refuse to use the GC at all? what if I DON´T WANT the GC to be compiled with my program and still wan´t to use new & delete operators, just like C++? (some kind of conditional GC), can I do that? Sorry for my ignorance, I'm already loving this language though... TomIs there a way to turn off the GC (Garbage Collector) in D?Sure. www.digitalmars.com/d/phobos/std_gc.htmlWhat if I want to manage all the memory by myself? Is this possible?Yes. You can even use C's malloc/free. See www.digitalmars.com/d/memory.html
Oct 27 2005
In article <djrbki$la6$1 digitaldaemon.com>, James Dunne says...Tomás Rossi wrote:So, I'm tied to use GC if I want to take advantage of any of the Phobos benefits. GC will be there, compiled with the rest no matter if I use it or not. :'( that's so sad. I must admit i have issues... DON'T FULLY TRUST GARBAGE COLLECTORS YET. On the other hand, i'm wondering, if D is a language that claims it can be used to write OSs (we all know OS code, or much of it, need to be very efficient), i dont think using GC in this code would be such a good idea. Probably OS would yet be implemented with malloc/free, because that way, you still have "some" control on what it happens... Ok, there is my mistrust in GC again. :P Regards TomIn article <djjic8$1ipg$2 digitaldaemon.com>, Walter Bright says...I wrote a phobos patch way back in the long-long ago that's probably outdated now... but it is theoretically a very simple patch. It simply ripped out the GC implementation and used C's malloc and free; naively I might add. Most of phobos is coded with use of the GC in mind, and is quite memory-leaky without it. All the GC related code is in src/phobos/internal/gc/."Tomás Rossi" <Tomás_member pathlink.com> wrote in message news:djj8qd$1ain$1 digitaldaemon.com...When disabling GC (std.gc.disable()) I just inhibit the GC cycles but, what if I refuse to use the GC at all? what if I DON´T WANT the GC to be compiled with my program and still wan´t to use new & delete operators, just like C++? (some kind of conditional GC), can I do that? Sorry for my ignorance, I'm already loving this language though... TomIs there a way to turn off the GC (Garbage Collector) in D?Sure. www.digitalmars.com/d/phobos/std_gc.htmlWhat if I want to manage all the memory by myself? Is this possible?Yes. You can even use C's malloc/free. See www.digitalmars.com/d/memory.html
Oct 27 2005
In article <djs1hd$dkv$1 digitaldaemon.com>, Tomás Rossi says...In article <djrbki$la6$1 digitaldaemon.com>, James Dunne says...Well, as stated before, with D you can use malloc/free as much as you want and even develop a lib. with non-GC'd functions when it makes sense (and take advantage of the GC for the rest) or for that matter just use C libraries when limited in this area. I used to feel the same about the GC as you do, but have come around to believe that a good GC can perform really well if the programmer doesn't abuse it. The primary problem with Java and .Net software is that the GC *makes* it easy to 'abuse' and also because of some language of their features like not allowing OOP UDT's to be allocated on the stack as C++ and D do. allocator/GC system and benchmark allocating a bunch of strings and UDT objects with it, and then do the same with equivalent (heap alloc) code in C++. In many cases, the GC will perform at least as well -- even when enough memory is allocated to force a couple of GC's during the test. D's GC is non-sophisticated because it is immature, but it'll improve to the not sooner. Besides, D has things like stack-allocated UDT's, easy array slicing, overrideable new/delete and de/allocators and copy-on-write library functions that make things a lot easier on a GC than Java and/or .Net; so a slow GC is less likely to cause as many problems.Tomás Rossi wrote:So, I'm tied to use GC if I want to take advantage of any of the Phobos benefits. GC will be there, compiled with the rest no matter if I use it or not. :'( that's so sad. I must admit i have issues... DON'T FULLY TRUST GARBAGE COLLECTORS YET. On the other hand, i'm wondering, if D is a language that claims it can be used to write OSs (we all know OS code, or much of it, need to be very efficient), i dont think using GC in this code would be such a good idea. Probably OS would yet be implemented with malloc/free, because that way, you still have "some" control on what it happens... Ok, there is my mistrust in GC again. :P Regards TomIn article <djjic8$1ipg$2 digitaldaemon.com>, Walter Bright says...I wrote a phobos patch way back in the long-long ago that's probably outdated now... but it is theoretically a very simple patch. It simply ripped out the GC implementation and used C's malloc and free; naively I might add. Most of phobos is coded with use of the GC in mind, and is quite memory-leaky without it. All the GC related code is in src/phobos/internal/gc/."Tomás Rossi" <Tomás_member pathlink.com> wrote in message news:djj8qd$1ain$1 digitaldaemon.com...When disabling GC (std.gc.disable()) I just inhibit the GC cycles but, what if I refuse to use the GC at all? what if I DON´T WANT the GC to be compiled with my program and still wan´t to use new & delete operators, just like C++? (some kind of conditional GC), can I do that? Sorry for my ignorance, I'm already loving this language though... TomIs there a way to turn off the GC (Garbage Collector) in D?Sure. www.digitalmars.com/d/phobos/std_gc.htmlWhat if I want to manage all the memory by myself? Is this possible?Yes. You can even use C's malloc/free. See www.digitalmars.com/d/memory.html
Oct 27 2005
In article <djs827$jjj$1 digitaldaemon.com>, Dave says...In article <djs1hd$dkv$1 digitaldaemon.com>, Tomás Rossi says...Do you mean that not allowing you to allocate your objects in the stack is the abuse? Is there another way you can abuse of GC?In article <djrbki$la6$1 digitaldaemon.com>, James Dunne says...Well, as stated before, with D you can use malloc/free as much as you want and even develop a lib. with non-GC'd functions when it makes sense (and take advantage of the GC for the rest) or for that matter just use C libraries when limited in this area. I used to feel the same about the GC as you do, but have come around to believe that a good GC can perform really well if the programmer doesn't abuse it. The primary problem with Java and .Net software is that the GC *makes* it easy to 'abuse' and also because of some language of their features like not allowing OOP UDT's to be allocated on the stack as C++ and D do.Tomás Rossi wrote:So, I'm tied to use GC if I want to take advantage of any of the Phobos benefits. GC will be there, compiled with the rest no matter if I use it or not. :'( that's so sad. I must admit i have issues... DON'T FULLY TRUST GARBAGE COLLECTORS YET. On the other hand, i'm wondering, if D is a language that claims it can be used to write OSs (we all know OS code, or much of it, need to be very efficient), i dont think using GC in this code would be such a good idea. Probably OS would yet be implemented with malloc/free, because that way, you still have "some" control on what it happens... Ok, there is my mistrust in GC again. :P Regards TomIn article <djjic8$1ipg$2 digitaldaemon.com>, Walter Bright says...I wrote a phobos patch way back in the long-long ago that's probably outdated now... but it is theoretically a very simple patch. It simply ripped out the GC implementation and used C's malloc and free; naively I might add. Most of phobos is coded with use of the GC in mind, and is quite memory-leaky without it. All the GC related code is in src/phobos/internal/gc/."Tomás Rossi" <Tomás_member pathlink.com> wrote in message news:djj8qd$1ain$1 digitaldaemon.com...When disabling GC (std.gc.disable()) I just inhibit the GC cycles but, what if I refuse to use the GC at all? what if I DON´T WANT the GC to be compiled with my program and still wan´t to use new & delete operators, just like C++? (some kind of conditional GC), can I do that? Sorry for my ignorance, I'm already loving this language though... TomIs there a way to turn off the GC (Garbage Collector) in D?Sure. www.digitalmars.com/d/phobos/std_gc.htmlWhat if I want to manage all the memory by myself? Is this possible?Yes. You can even use C's malloc/free. See www.digitalmars.com/d/memory.htmlallocator/GC system and benchmark allocating a bunch of strings and UDT objects with it, and then do the same with equivalent (heap alloc) code in C++. In many cases, the GC will perform at least as well -- even when enough memory is allocated to force a couple of GC's during the test.I don't know if i can benchmark a compiled language (C++) vs. an intepreted one me to extract any conclusions. Even though the comparisons between a GCd language and a non-GCd one would be done in that case, i wouldn't really know when the differences would be caused by GC or by the intrinsic efficiency due to compiled/interpreted nature of each language.D's GC is non-sophisticated because it is immature,I didn't know this... but now that you warned me, i have to tell you: "that makes me feel so relieved!" :Pbut it'll improve to the not sooner.Hope so.Besides, D has things like stack-allocated UDT's, easy array slicing, overrideable new/delete and de/allocators and copy-on-write library functions that make things a lot easier on a GC than Java and/or .Net; so a slow GC is less likely to cause as many problems.Ok, i know i'm a little paranoid and obsessive about efficiency when programming, but all the other very nice features of D that you're referring to are just the ones that i like very much and that's why i'm worried about the features that makes me "distrust" of the language performance (e.g. the GC). I have no doubts i will make use of it (the GC) in the most of my future D projects, but it would be SO NICE if it could be completely turned off in a transparent way for other kind of projects (and also have a non-GC-based Phobos, i know this will not happen, it's an utopia, but luckily dreaming is still free) :D. Regards Tom
Oct 28 2005
In article <djtcfe$1qr4$1 digitaldaemon.com>, Tomás Rossi says...In article <djs827$jjj$1 digitaldaemon.com>, Dave says...Well, that's part of it - just about everything has to be allocated on the heap, but in C++ you can allocate class objects on the stack and D you can use structs because the GC makes it easy to "allocate and forget" about managing resources. I suppose this will happen with any GC, but with Java it's really been hard on its performance reputation.In article <djs1hd$dkv$1 digitaldaemon.com>, Tomás Rossi says...Do you mean that not allowing you to allocate your objects in the stack is the abuse? Is there another way you can abuse of GC?In article <djrbki$la6$1 digitaldaemon.com>, James Dunne says...Well, as stated before, with D you can use malloc/free as much as you want and even develop a lib. with non-GC'd functions when it makes sense (and take advantage of the GC for the rest) or for that matter just use C libraries when limited in this area. I used to feel the same about the GC as you do, but have come around to believe that a good GC can perform really well if the programmer doesn't abuse it. The primary problem with Java and .Net software is that the GC *makes* it easy to 'abuse' and also because of some language of their features like not allowing OOP UDT's to be allocated on the stack as C++ and D do.Tomás Rossi wrote:So, I'm tied to use GC if I want to take advantage of any of the Phobos benefits. GC will be there, compiled with the rest no matter if I use it or not. :'( that's so sad. I must admit i have issues... DON'T FULLY TRUST GARBAGE COLLECTORS YET. On the other hand, i'm wondering, if D is a language that claims it can be used to write OSs (we all know OS code, or much of it, need to be very efficient), i dont think using GC in this code would be such a good idea. Probably OS would yet be implemented with malloc/free, because that way, you still have "some" control on what it happens... Ok, there is my mistrust in GC again. :P Regards TomIn article <djjic8$1ipg$2 digitaldaemon.com>, Walter Bright says...I wrote a phobos patch way back in the long-long ago that's probably outdated now... but it is theoretically a very simple patch. It simply ripped out the GC implementation and used C's malloc and free; naively I might add. Most of phobos is coded with use of the GC in mind, and is quite memory-leaky without it. All the GC related code is in src/phobos/internal/gc/."Tomás Rossi" <Tomás_member pathlink.com> wrote in message news:djj8qd$1ain$1 digitaldaemon.com...When disabling GC (std.gc.disable()) I just inhibit the GC cycles but, what if I refuse to use the GC at all? what if I DON´T WANT the GC to be compiled with my program and still wan´t to use new & delete operators, just like C++? (some kind of conditional GC), can I do that? Sorry for my ignorance, I'm already loving this language though... TomIs there a way to turn off the GC (Garbage Collector) in D?Sure. www.digitalmars.com/d/phobos/std_gc.htmlWhat if I want to manage all the memory by myself? Is this possible?Yes. You can even use C's malloc/free. See www.digitalmars.com/d/memory.htmlJIT's are getting pretty good, and since your dealing with heap allocation that will be the bottleneck so the comparison will tell you more about the allocator/GC than the machine code optimizations.allocator/GC system and benchmark allocating a bunch of strings and UDT objects with it, and then do the same with equivalent (heap alloc) code in C++. In many cases, the GC will perform at least as well -- even when enough memory is allocated to force a couple of GC's during the test.I don't know if i can benchmark a compiled language (C++) vs. an intepreted one me to extract any conclusions. Even though the comparisons between a GCd language and a non-GCd one would be done in that case, i wouldn't really know when the differences would be caused by GC or by the intrinsic efficiency due to compiled/interpreted nature of each language.That's a good thing IMHO - I think "slowness" is a "bug" and usually a lot harder to fix than most other bugs once a large program is getting close to being done. Users complain about crashes, but they *bitch* about slowness <g>D's GC is non-sophisticated because it is immature,I didn't know this... but now that you warned me, i have to tell you: "that makes me feel so relieved!" :Pbut it'll improve to the not sooner.Hope so.Besides, D has things like stack-allocated UDT's, easy array slicing, overrideable new/delete and de/allocators and copy-on-write library functions that make things a lot easier on a GC than Java and/or .Net; so a slow GC is less likely to cause as many problems.Ok, i know i'm a little paranoid and obsessive about efficiency whenprogramming, but all the other very nice features of D that you're referring to are just the ones that i like very much and that's why i'm worried about the features that makes me "distrust" of the language performance (e.g. the GC). I have no doubts i will make use of it (the GC) in the most of my future D projects, but it would be SO NICE if it could be completely turned off in a transparent way for other kind of projects (and also have a non-GC-based Phobos, i know this will not happen, it's an utopia, but luckily dreaming is still free) :D. Regards Tom
Oct 29 2005
In article <djvt02$1a1b$1 digitaldaemon.com>, Dave says...In article <djtcfe$1qr4$1 digitaldaemon.com>, Tomás Rossi says...So, if I explicitly delete my objects most of the times, that would be a wise use of GC? (namely that would be non-abusive use of GC?). TomIn article <djs827$jjj$1 digitaldaemon.com>, Dave says...Well, that's part of it - just about everything has to be allocated on the heap, but in C++ you can allocate class objects on the stack and D you can use structs because the GC makes it easy to "allocate and forget" about managing resources. I suppose this will happen with any GC, but with Java it's really been hard on its performance reputation.In article <djs1hd$dkv$1 digitaldaemon.com>, Tomás Rossi says...Do you mean that not allowing you to allocate your objects in the stack is the abuse? Is there another way you can abuse of GC?In article <djrbki$la6$1 digitaldaemon.com>, James Dunne says...Well, as stated before, with D you can use malloc/free as much as you want and even develop a lib. with non-GC'd functions when it makes sense (and take advantage of the GC for the rest) or for that matter just use C libraries when limited in this area. I used to feel the same about the GC as you do, but have come around to believe that a good GC can perform really well if the programmer doesn't abuse it. The primary problem with Java and .Net software is that the GC *makes* it easy to 'abuse' and also because of some language of their features like not allowing OOP UDT's to be allocated on the stack as C++ and D do.Tomás Rossi wrote:So, I'm tied to use GC if I want to take advantage of any of the Phobos benefits. GC will be there, compiled with the rest no matter if I use it or not. :'( that's so sad. I must admit i have issues... DON'T FULLY TRUST GARBAGE COLLECTORS YET. On the other hand, i'm wondering, if D is a language that claims it can be used to write OSs (we all know OS code, or much of it, need to be very efficient), i dont think using GC in this code would be such a good idea. Probably OS would yet be implemented with malloc/free, because that way, you still have "some" control on what it happens... Ok, there is my mistrust in GC again. :P Regards TomIn article <djjic8$1ipg$2 digitaldaemon.com>, Walter Bright says...I wrote a phobos patch way back in the long-long ago that's probably outdated now... but it is theoretically a very simple patch. It simply ripped out the GC implementation and used C's malloc and free; naively I might add. Most of phobos is coded with use of the GC in mind, and is quite memory-leaky without it. All the GC related code is in src/phobos/internal/gc/."Tomás Rossi" <Tomás_member pathlink.com> wrote in message news:djj8qd$1ain$1 digitaldaemon.com...When disabling GC (std.gc.disable()) I just inhibit the GC cycles but, what if I refuse to use the GC at all? what if I DON´T WANT the GC to be compiled with my program and still wan´t to use new & delete operators, just like C++? (some kind of conditional GC), can I do that? Sorry for my ignorance, I'm already loving this language though... TomIs there a way to turn off the GC (Garbage Collector) in D?Sure. www.digitalmars.com/d/phobos/std_gc.htmlWhat if I want to manage all the memory by myself? Is this possible?Yes. You can even use C's malloc/free. See www.digitalmars.com/d/memory.htmlJIT's are getting pretty good, and since your dealing with heap allocation that will be the bottleneck so the comparison will tell you more about the allocator/GC than the machine code optimizations.allocator/GC system and benchmark allocating a bunch of strings and UDT objects with it, and then do the same with equivalent (heap alloc) code in C++. In many cases, the GC will perform at least as well -- even when enough memory is allocated to force a couple of GC's during the test.I don't know if i can benchmark a compiled language (C++) vs. an intepreted one me to extract any conclusions. Even though the comparisons between a GCd language and a non-GCd one would be done in that case, i wouldn't really know when the differences would be caused by GC or by the intrinsic efficiency due to compiled/interpreted nature of each language.That's a good thing IMHO - I think "slowness" is a "bug" and usually a lot harder to fix than most other bugs once a large program is getting close to being done. Users complain about crashes, but they *bitch* about slowness <g>D's GC is non-sophisticated because it is immature,I didn't know this... but now that you warned me, i have to tell you: "that makes me feel so relieved!" :Pbut it'll improve to the not sooner.Hope so.Besides, D has things like stack-allocated UDT's, easy array slicing, overrideable new/delete and de/allocators and copy-on-write library functions that make things a lot easier on a GC than Java and/or .Net; so a slow GC is less likely to cause as many problems.Ok, i know i'm a little paranoid and obsessive about efficiency whenprogramming, but all the other very nice features of D that you're referring to are just the ones that i like very much and that's why i'm worried about the features that makes me "distrust" of the language performance (e.g. the GC). I have no doubts i will make use of it (the GC) in the most of my future D projects, but it would be SO NICE if it could be completely turned off in a transparent way for other kind of projects (and also have a non-GC-based Phobos, i know this will not happen, it's an utopia, but luckily dreaming is still free) :D. Regards Tom
Oct 29 2005
Tomás Rossi wrote:Is there a way to turn off the GC (Garbage Collector) in D? What if I want to manage all the memory by myself? Is this possible? TomGC is not as much as a bottleneck as you might think. Write some memory intensive programs and compare them to C++.
Oct 27 2005