I saw a post a week or so ago, here or somewhere else, that defined what wired, active, inactive, and free ram means.
My understanding is inactive is basically free ram that can be used by any app.
I did a search and came across this explaination:
"Inactive" RAM contains data that can be thrown away at any time. For example, it could contain cached data from your harddisk. If an application reads a file from the harddisk, that file will be cached in "Inactive" RAM in case you read it again later. Or if you quit an application, the memory that held the code will be "Inactive". If you start the same application again, it need not be read from the harddisk, the OS just turns the Inactive memory into active memory."
Basically I dont think there is any big need to flush the inactive ram.
edit - google search turned up
From Apple's Support Pages:
Inactive memory
This information is no longer being used and has been cached to disk, but it will remain in RAM until another application needs the space. Leaving this information in RAM is to your advantage if you (or a client of your computer) come back to it later.
Free memory
This memory is not being used.
What does all this mean?
This means you shouldn't worry when the Free memory is low. The only time Free memory should be high is right after the computer starts up. As you use applications or services, memory is used and transitions to Inactive. Applications that need more memory will take from the Inactive, but the Inactive is there just in case you need it again. If the combination of Free and Inactive is very low, then you might need more memory.
