Jordan wrote:Ohhhh.... I missed where you mentioned in the first post that you were talking about
inactive memory.
Here is an apple.com article that describes what inactive memory is, and why you shouldn't worry about it being high.
thank you for the link.
According to Apple, large amount of inactive memory should not be a concern. Agree. Clearly explained by Apple.
This, however, does not explain the effect of huge size of inactive memory on system performance.
When the amount of Inactive memory orders of magnitude larger than the amount of free memory, system performance degrades significantly.
According to Apple, MAC OS X would request more memory to be converted from inactive to free if needed. This does not happen however. The current version of transmission (1.33 build 6594) seems to have same problem, but in smaller magnitude. For Example, today, after the transmission run for few hours and was properly terminated, the amount of inactive system memory in my system equaled approx 30% of total memory. This is over 1Gb in my 4G system.
Now, notice that when I launch the Vmware Fusion which is a virtual machine where I run Windows XP inside, the amount of free memory is next to zero (I can dynamically allocate any size of memory to Virtual machine. In my case it 1.5Gb). This is the memory-hungry application. I assume that in this scenario MAC OS X desperately needs more memory for OS X environment. For some reason MAC OS X is unable to release more free memory from that 1+ Gb chunk of "Inactive" memory left behind by Transmission client. I remain suspicious whether Transmission handles it properly. In fact I do believe that an old bug is not completely fixed to date.
In brief: in my scenario, after transmission run for few hours 1Gb remains inactive, next I launch Windows XP as a virtual machine. The result: almost zero of free memory available to Mac OS X, degraded performance, and 1Gb+ of memory still inactive

. Does not sound normal to me. So far i have not notice any other application leaving so much inactive memory behind as much as transmission leaves behind.
Note: Normally Virtual Windows XP does not noticeably affect the performance of my MacBook Pro. I am talking about decreased performance with huge chunk of inactive memory left behind by transmission vs same conditions but without having transmission run for hours prior to launching memory hungry tasks.
Something to think about here.
Please don't get me wrong. I like the application, not trying to blame developers, but respect their collective efforts. Could be just "MAC OS X problem" ???. Just see the issue that needs some more close attention in my opinion.
Thanks,
Pavel