Barton wrote: "There were two redbooks this year that looked at many performance issues. If anything, they were productive in finding performance issues that needed to be addressed."
I'm not addressing "tuning", but rather taking issue with the fact that there is very little recent performance and capacity information. A lot of measurements were done early, s/390z Linux was categorized, then a series of assumptions have become the mythology of Linux on zSeries. Since then, zSeries has changed a lot. One of things that happens when machines become faster and bigger is that they enable more applications on that platform. Until the G6, CMOS techonolgy was even slower than the bipolar technology that it replace. Now, the zSeries has caught up with and now exceeds its previous capabilities spurred on by the competition of intel and Unix processors. We need to evaluate some of the assumptions we made early on (3 years ago!). For example: August, 2003, share http://www.linuxvm.org/present/index.html Thoss's report on performance is about the lastest there is: z900 z216, F20 shark, ESCON/FICON, gigabit ethernet, 2.4.7 or 2.4.17 kernel, 31 bit. Currently available to the customer: z990, 800 shark, FICON, 2.4.21 kernel, hipersockets, 64 bit. (some of the test in Thoss's report were memory constrained in a 31 bit environment). Also, - the redbooks emphasize overall VM tuninig with really very little information about tuning Linux - especially if you have to run in an LPAR - a dearth of information on things like DB2, websphere - lots of reports on how zseries scaled up to an "equivalent" intel, but not really very much of what happens when zseries scales BEYOND intel (both in CPs and I/O) - large transactions volumes and rates. ===== Jim Sibley Implementor of Linux on zSeries in the beautiful Silicon Valley "Computer are useless.They can only give answers." Pablo Picasso __________________________________ Do you Yahoo!? The New Yahoo! Shopping - with improved product search http://shopping.yahoo.com
