On Sun, Aug 30, 2009 at 3:43 AM, Peter Teoh <[email protected]> wrote:
> Thank you Minchan. You made me curious now...:-). > > On Sat, Aug 29, 2009 at 9:37 PM, Minchan Kim<[email protected]> wrote: > > Hi, Peter. > > > > On Sun, Aug 30, 2009 at 9:20 AM, Peter Teoh<[email protected]> > wrote: > >> The papers are located here: > >> > >> http://www.linuxsymposium.org/2009/ls-2009-proceedings.pdf > >> > >> I have not read any papers yet. But given limited amount of time - > >> which papers do u think are the interesting one to read? And perhaps > > > > In my case, I will take a "Increasing memory density by using KSM". > > > > Have not really pursued deeply other than: > > http://lkml.org/lkml/2009/4/19/210 > > But conceptually: > > a. what is the criteria of deciding when two piece of memory are > identical? (if it is byte-for-byte comparison then performance will > be seriously disastrous?) > you dont need to do that everytime ... think hashes... and only if they match go ahead compare byte-by-byte > > b. and after memory memory coalescing....due to "identical" memory - > necessarily this is applicable to read-only memory right? (if not > then it may be modified later....and u need to trigger copy-on-write > mechanism to duplicate the memory piece....lots of overheads i > supposed). > cow it is. > > c. but isn't it very dangerous - even though it is read-only....one > KVM client can actually modify the memory (just set_memory_rw() to > turn it read-write, and then write to it.....and effectly the entire > chain of KVM effectively is compromised via having a corrupted piece > of memory? but then again i am suspecting i am completely > wrong.....as logically KVM client should not be able to change > memory's PTE attribute just purely using set_memory_rw() as a VM > client. if this is true, then it means that u need duplication of > the pagetables to describes the memory attributes - one for the VM > client, and one for the VM host? Sorry....completely newbie... > > d. on the other hand....if it is really permanently set to > readonly....and a KVM client after calling set_memory_rw()...still > will NOT be able to set the memory read-write....then immediately the > KVM client can deduce something about the server....eg....VM > environment...as real x86 hardware does not have memory readonly > setting capability... > > >> one-liners comment on why? > > > > There is no special reason. If I have to say, > > > > 1. I have a interesting in mm, > > 2, KSM is one of hot topics these days. > > 3. KSM can affect both server and embedded device > > 4. I know authour's many contiribution in linux kernel so that I don't > > doubt paper's quality. > > > > :) > > > Thank you for the sharing.... > > -- > Regards, > Peter Teoh > > -- > To unsubscribe from this list: send an email with > "unsubscribe kernelnewbies" to [email protected] > Please read the FAQ at http://kernelnewbies.org/FAQ > >
