![]() | |||||||||||||
Messages in this thread |
Joe Korty wrote: > > [ repost - first attempt failed to get out ] > > > > Is the "don't reuse an ID for some time" requirement still there? > > > > I don't see the need for the "don't reuse an ID for some > > time" thing and it looked like what Jim had messed up the > > book keeping AND it also looked like it failed to actually > > work. All of this convinced me that the added complexity > > was just not worth it. > > A thought: any algorithm that fails to "reuse an ID for some time" > can be converted into one that does by tweaking the algorithn to > return an ID with fewer bits and putting a counter (bumped on each > fresh allocation of that ID) in the remaining bits. Or, one can go > stateless and achieve an "almost never reuse an ID for some time" by > instead inserting a freshly generated pseudo-random number in the > unused ID bits. > With out going into a lot of detail, since I don't think I need such an animal, one would need to keep the actual id somewhere (either the node or in what it pointed to). Perhaps a less costly way would be to keep a sequence number, say the number of items allocated so far and inserting that. I think one would want to make sure this is not a power of 2, but this may not be needed as the first freeing would generate an indexing of the number WRT to the id. -- George Anzinger george@mvista.com High-res-timers: http://sourceforge.net/projects/high-res-timers/ Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | ||||||||||||
| Last update: 2005-03-22 12:31 [W:0.369 / U:0.060 seconds] ©2003-2008 Jasper Spaans | |||||||||||||