> Does anyone have a 'Rule-of-thumb' for sizing Linux guests running > under z/VM. Especially > Virtual Memory sizes.
Here's what I do: 0) Create a test machine with one virtual CPU. 1) Make sure you have at least 2 VDISK swap areas and (optionally) a real disk swap area configured for the test machine. 2) Start with 256M of virtual storage. If it's a Java app or other known memory pig, start with 768M. 3) Install the application 4) Run a realistic test workload. Observe the application and the system while running. Run for at least an hour to let transients and caches initialize and come to a steady state. 5) If the application runs OK, leave it there, and go to step 7. 6) If the application doesn't run OK, look at the swap usage. If more than 10% of the first VDISK swap area is in use, stop the test, shutdown the machine and add 128M of virtual storage. Repeat from step 4. 7) Create the real virtual machine using the parameters you derived from 0-6. Install the application, and put the real data in it. 8) Declare victory and go to the pub. Apps will behave differently in this environment, so your guaranteed best bet is the iterative method above, coupled with your favorite VM performance monitor. -- db PS - Step 8 is my favorite. 8-) ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
