Le 04/04/2016 01:28, Collin Anderson a écrit : > So, I used to be into game development, I was big on writing my own engines > from scratch in C++. > This exact memory management problem is one encountered very frequently in > such projects. Any > game developer lives by this mantra when it comes to memory management: never > fragment the heap. > > > The reduction in memory usage cannot justify the system-wide impacts of heap > fragmentation and > memory manager overhead caused by frequent allocation and freeing of large > blocks. The #if 1 on > line 178 should always be a #if 0, in my opinion. The comment says, 'there > is no point in > holding a large amount of memory when there is no use for it." Of course > there is a use for it. > There just isn't a use for it right that instant, but if that much > simultaneous memory was at one > point needed, then its safe to assume it will be needed again, so just hold > on to it until then. > Yes, that is wasteful, but it is less wasteful than the system-wide > performance toll that > significant heap fragmentation can cause. The reduced memory usage is simply > not worth the cost. > It is better to consume the additional memory. > > As for improving cached_container, believe it or not, I actually have a > container class I wrote > years ago that I am rather proud of, it was designed to manage large terrain > meshes (I was > writing my own ROAM terrain rendering engine) and I am going to play around > and see if its > adaptable to KiCad. And if it is, I'll see if it is helpful. It might be I > just THINK it is > good, but isn't :). If I have anything useful to add or modify in that class > though, I'll do a > branch. > > Thanks! > >
Thanks for your help. I fully agree with you. However I am not the guy who wrote the cached container code. In rev 6661, I disable this deallocation/reallocation option (This change was suggested by Orson, the author of this code). It is not yet perfect. I still have this issue when switching off/on the Opengl GAL, because there is still a deallocation/reallocation memory It could be worth to see if your container class can help to fix this (very annoying and serious, because I ran out of memory on a PC with 4Gb of memory, with 256 Mbytes chunks only) issue. -- Jean-Pierre CHARRAS _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
