---------- Forwarded message ---------- From: Simeon Nifos <archwn...@googlemail.com> Date: Fri, Sep 26, 2008 at 10:12 AM Subject: Re: [laptop-discuss] Modern laptop hardware support To: Edward O'Callaghan <victoredwardocallaghan at gmail.com>
> Sorry Simeon, > That is all miss informed bull sh*t ! Hi Edward! Maybe ... To some extent ... > * Ubuntu has *not* complied its kernel in real time mode as default. Who said it has ... It provides though a precompiled kernelBLABLABLA-rt. It is in the repository and you can install it if you like. > * The RAM is not 'wasted' if it is helping your IO responsiveness > issues and as Desktops see very heavy IO usage these days then its > clearly a very good use of RAM. It is definitely wasted if you need it for other sort of things. Suppose you are running a RAM and FPU intensive application which needs 1.5GB. If lots of your RAM is used to cache your filesystem then this is not good. > * A real time kernel does *not* help in responsiveness issues but is > used for time critical situations such as embedded type systems and > will almost always preform extremely badly in a desktop situation > except maybe audio editing. > In answer to your question, yes you can put Solaris into real time mode using: > dispadmin -d RT which would be a bad idea. Well I need to do more testing and get back to you. > * ZFS does not eat up all your RAM and you can limit it if you really must.. > * IO bandwidth is the number one bottle neck on any x86/x64 system, > end of story. NO! It depends on the application. If you use things which access the disk 30hours per day then I agree. But if you are running FPU apps with lots of RAM utilization the I totally disagree. > Good luke writing a modern OS and software stack in ASM that is > non-portable highly architecture dependent and _then_ trying to debug > that. > > Oh and you didn't even email the list, you sent it to me. > Please have a *clue* instead of misinforming people. You may now thank > me for forwarding your email :p > > Thanks, > Edward. It is not a miracle that Suns Performance library is far superior than other optimized BLAS+Lapack Libraries like Intel-MKL and AMD ACML not to mention thread safety of the underlying algorithms. What I want to say is that SUN has invested on FileSystem Stuff and Disk IO. If you need something like this which is quite common is lots of lots of servers then that's fine. If you need it for something more sophisticated then try some other operating system instead. DTrace however is a nice tool years ahead anything else.
