Anyone else heard "swap must be 85% of RAM or you aren't using all of RAM"

[S.Rider]

I heard that from a contractor a month ago, but he's gone now and I can't verify where he got that information from.

[Dennis Handly]

It might be true if you don't have pseudo swap turned on.

[A. Clay Stephenson · Accepted solution]

That's nonsense, for 11.11 and down, you needed 25% of physical memory + swapmem_on = 1 (pseudoswap enabled) to fully utilize process space. 75% of physical memory can be counted as process reservation space (pseudoswap) + 25% device or filesystem swap gets you to 100%. For 11.23 and up, the fraction goes above 75%.

I have many systems trhat have much more memory than swap and they run just fine and can fully utilize memory. I bought all that memory so that I wouldn't have to swap.

Now, if swapmem_on = 0, you can reserve no more process space than you have actual swap space (device or filesystem).

[Pete Randall]

Sounds like a rule of thumb from a thumbless man to me.


Pete

[whiteknight]

Rider,

Check this documents on managing your swap space.

Estimating Your Swap Space Needs
http://docs.hp.com/en/B2355-90950/ch06s03.html

Hope this help
WK