On Thu, 17 Aug 2006 11:27:50 -0400, Alan Altmark <[EMAIL PROTECTED] > wrote:
>On Thursday, 08/17/2006 at 09:39 EST, Brian Nielsen ><[EMAIL PROTECTED]> wrote: >> >It certainly affects the size of the HSA *IF* that particular IOCDS i s >> >marked to allow dynamic updates. If you don't specify MAXDEV=, it >> >defaults to the maximum number of devices allowed by the processor. >That >> >means your HSA will be as large as it can possibly be. >> >> Does that mean that for a dynamic IOCDS I can change the size of the H SA >> by means of the MAXDEV parameter? For example, if I have only have 4K >> devices can I lower MAXDEV from 63K to 20K and thus recover some memor y >> from HSA and still leave lots of room for dynamic I/O changes? > >From my understanding of how the IOCDS and the HSA interact, yes. Thanks, that's been my understanding as well. >There is an HSA size estimator on ResourceLink. Look under "Tools". I've looked at the HSA estimation tool. The reported change in estimated HSA size is very small - going from 63K devices down to as low as 6K devices made only a 64M difference in HSA size. Dropping of the number o f LPARs from 6 to 1 made only another 64M difference. I would have expecte d a larger change. C'est la vie. Brian Nielsen
