On Wed, Sep 17, 2008 at 10:25:47AM +0200, Michael Gebetsroither wrote: > * Arno Wagner <arno@xxxxxxxxxxx> wrote: > > I have about 45% CPU on a very low end AMD Sempron(tm) > > Processor LE-1250 for 30MB/s. You probably should have > > bought faster cores instead of more. > > 30MB/s? > You know that even a single moderm SATA disk does 100MB/s streaming? Not really. Most reach close to 100MB/s at the start and go down to something like 50MB/s at the end. This was a very modern notebook disk (low power server) towards the end. > The problem is, that about 0.1% of the users have CPU's where one core > is capable of >100MB/s of even AES 128. The number is irrelevant. Linear performance is not a major factor for most users, as long as it is not impacted to dramatically. In addition, most users do not use Linux and of those that do, most do not use disk encryption. > The _real_ problem behind all these is much bigger. For the majority of > the users the single-threaded performance will stagnate (or even > decrease) in the next years So, they bought not what was actually fastest. For most, it will still be more than fast enough. > > Incidentially, I believe your request has about zero prospect > > of being sucessful. It is a lot of effort for basically > > very few people having any gain. I would not do it unless fully > > paid, but thet _wpuld_ be expensive. > > As the fix with the current situation is quite simple (put the raid on > top of dm-crypt) it's not the biggest problem, yes. Well, if it is RAID, hat is a good solution. However for single disks that does not work. I originally thought this was about an encrypted fast flash disk. > But as stated above, moderm disks are faster than one core could encrypt > with AES128. > And the situation only gets worse. However the implementation issue also dos enot get better. Probably thios is not even a thing that dm-crypt could solve, but would require a makor filesystem layer rewrite. One the other side, the problem is not really an issue, even though some people seem to feel strongly about it. Arno -- Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@xxxxxxxxxxx GnuPG: ID: 1E25338F FP: 0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F ---- Cuddly UI's are the manifestation of wishful thinking. -- Dylan Evans If it's in the news, don't worry about it. The very definition of "news" is "something that hardly ever happens." -- Bruce Schneier --------------------------------------------------------------------- dm-crypt mailing list - http://www.saout.de/misc/dm-crypt/ To unsubscribe, e-mail: dm-crypt-unsubscribe@xxxxxxxx For additional commands, e-mail: dm-crypt-help@xxxxxxxx
