A few comments on QUICKDSP; some opinion, some fact. I tend to look at QUICKDSP in three lights: 1. As Barton mentioned any guest/server that another guest depends on. He once used the phrase 'anything that is an extension of the operating system (VM)' should have quickdsp. Network, security, file systems, etc. 2. Production guests or mission critical, i.e. any guest that if it were to stop you could get a phone call from someone with authority to fire you. "Production" gets to be gray because some 'development' guests consider themselves production because they produce code. :-) 3. The more predictable or reliable a guest is, the more likely I am to give it QUICKDSP. Use of QUICKDSP doesn't really 'disable' the scheduler, it just tells the scheduler to behave differently in one aspect. When you use QUICKDSP you are saying, I (the sys programmer) am taking responsibility that this guest will not over-burden the available real resources (i.e. avoid thrashing). Test systems, by their nature, are not predictable so I tend not to give them QUICKDSP.
So the two approaches (three when you do it in combination) are 1) use of QUICKDSP and 2) adjust STORBUF settings. I usually recommend considering both (after first revisiting the size of the guests as Adam recommended). When adjusting STORBUF there are some 'rules of thumb' floating around out there, but it is worthwhile understanding what the numbers mean. See the documentation or Malcolm's write up: http://www.marist.edu/htbin/wlvtype?LINUX-VM.30359 I do not generally recommend setting all three values in STORBUF the same, especially if you have a mixed environment with interactive CMS guests. It may be perfectly acceptable in pure Linux guest environment. Also, just to clarify. QUICKDSP does not disable the scheduler's ability to effectively set priorities based on Share settings. Bill Bitner - VM Performance Evaluation - IBM Endicott - 607-429-3286 ---------------------------------------------------------------------- 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
