Maxxuss Tuning For Mac
- Jan 10, 2006 - Maxxuss Tuning, Measurements and Technical Information for Mac OS X 10.4.3 8F1111 and 8F1111A Tiger on the Intel/x86 Platform.
- The Tuner contains the following parameters: Graphic Tuning display: Shows the pitch of the note in cents.When the needle is centered in the display, the note is in tune. When the needle is left of center, the note is flat; when the needle is right of center, the note is sharp.
Car tuning software for mac Car tuning software free download for Mac OS X (Mac) Free Download Ecu Tuning Software - suggestions TunerPro and TunerPro RT - Professional Automobile Laptop Tuning software - MY350Z.
Here's some more info about this from this site: UBC and sysctl (top) From what I have gathered on a variety of lists, the most commonly 'tweaked' part of the system via sysctl is the Unified Buffer Cache (UBC). In a really great email a developer made some excellent recommendations for tuning a system with UBC, this section will peruse that for the example. Following along with the maxfiles example above, even though there can now be a larger amount of open files, there still may be more that can be done to make the system run faster. Since more files can be opened, it stands to reason that it would be good if the caching were optimized as well. In the case of this machine, there is a decent amount of RAM (256MB) that despite a lot of low level activity (such as editing and small compiles) is not being utilized to its full potential. This means that the buffer cache could probably be expanded, thereby making performance better since more would be in the cache versus rereading from disk.
Now, a word of warning, it is of course possible to raise the size to a point where getting a cache hit is taking too long, but as has been well documented, that number seems to be fairly high 1. So what is the parameter?
It is kern.maxvnodes and in the case of this machine, 38k was used which gave a pretty decent performance boost. In general, it has been seen that a kern.maxvnodes operates well when the size is set to between 1/6 to 1/4 of the amount of RAM (depending on what the system is being used for). Something doesn't jive here though.
Maxxuss Tuning For Mac Pro
I am a prime candidate for this - with over 1.2G of RAM. Following the info at the discussions, I tested to see if it would be beneficial using these commands: First to see if the change will be beneficial, wait unto your system is being sluggish and in a terminal window do the following commands: pstat -T sysctl kern.maxvnodesThe numbers came up almost identical - I think a difference of 1. So I hardwired the tuning to the /etc/rc as explained and then rebooted. Running the test after rebooting and enabling this hack I get:% pstat -T 86714 vnodes swapmode is not (yet) available under Mach% sysctl kern.maxvnodes kern.maxvnodes = 86720 WOW! A difference of 6.
Is that supposed to be good??? I personally have not really noticed any performance increase either.
I'm a bit suspicious of this too. I've tried it out and from everything I can tell, the number of vnodes in use will never shrink significantly. I think I only saw vnode shrinkage when I actually deleted recently touched files. Being that is never shrinks, any system with any maxvnodes setting will eventually hit the 99% usage mark, making this a useless metric for determining that your maxvnodes amount is too low.
Also, I've been searching the web, and I still haven't found a clear definition of exactly what a vnode is cachine? Is it just filesystem metadata, or does this somehow factor into caching the file contents as well? Does a 6 gig file still take only one vnode slot when it is cached?
How do we measure the effectiveness of the unified buffer cache? Is that what the hitrate value is in vmstat? Does increasing the maxvnodes help better utilize unused RAM? I looked at our CVS server and it is hardly using it's RAM and could maybe take advantage of this.
The machine has 1.5 gig of RAM and 1.1 gig of it is still free after 18 days of uptime. I suspect that if OS X hasn't utilized it after 2 weeks, it's not likely to start using it soon. It would probably better be used for disk caching. If sure would be nice if Apple would document the low levels of the system a bit better:-).
Works just fine in Panther. I say 'works' meaning it causes no ill effects. Whether it actually does anything is anyones guess. Just a note though - if you are running the default crontasks for os x that run at 3am or so - all bets are off. This process completely whacks out maxvnodes and when you get up in the morning it is ALWAYS at 100%.
I guess I shouldn't say 'whacks out' what I mean is - it completely obliterates any maxvnodes tuning you have done. Something about touching/accessing hundreds of files so I've read. I found the following discussion in the archives of the Darwin development email list: The writer is/was apparently one of Apple's kernel developers and so presumably knows what he/she is talking about. Summary: Increasing the value of maxvnodes will increase the number of files that get cached in RAM. This will make subsequent access to those files much faster. But the downside is that more of your RAM will be used up for this disk caching and thus you will have less RAM available for normal application use.Therefore you should only consider increasing maxvnodes if you always have lots of 'free memory' as shown in 'top' or 'Activity Monitor', and if you hardly ever get pageouts (also shown in 'top' or 'Activity Monitor').
The default value is a compromise that is expected to result in the best overall performance for people using OS X as a 'desktop OS' - i.e. For running GUI applications, etc.
If you are running OS X primarily for use as a server, or if your usage differs significantly from the norm, you might find it useful to tune the maxvnodes number. But only if you have a lot more RAM than is needed for the apps you run!