The following message is a courtesy copy of an article that has been posted to bit.listserv.ibm-main,alt.folklore.computers as well.
Anne & Lynn Wheeler <[EMAIL PROTECTED]> writes: > now cp67 & vm370 did strictly account for nearly every clock tick > ... back when MVS "cature ratio" typically ran around 40-50 percent > ... but could be less (and the "uncaptured" time was essentially all > kernel or other system services). re: http://www.garlic.com/~lynn/2007g.html#80 IBM to the PCM market http://www.garlic.com/~lynn/2007g.html#81 IBM to the PCM market http://www.garlic.com/~lynn/2007g.html#82 IBM to the PCM market again it is how you are accounting for the values. in typical vm/cms environment the supervisor/problem split means that all of the supervisor is in the vm kernel and all of problem is in the CMS application (cms "kernel" pathlengths mostly being almost negligible). however, nearly all of vm kernel supervisor is directly accounted to application virtual address spaces ... with the remaining supervisor still be accounted for, but against a "special" system task. now a lot more of unix work on behalf of applications show up as "straight" supervisor time ... for instance all of the tcp/ip stack typically shows up in a (unix) kernel ... and shows up as supervisor. However, a typical unix tcp/ip pathlength is significantly shorter than any corresponding mvs pathlength thru VTAM (while the accounting for instructions may be radically different ... the number of instructions to implement similar function can be orders of magnitude less). for other drift some posts mentioning microkernel efforts to get tcp/ip stack out of kernel space. http://www.garlic.com/~lynn/2006p.html#13 What part of z/OS is the OS? http://www.garlic.com/~lynn/2006s.html#7 Very slow booting and running and brain-dead OS's? http://www.garlic.com/~lynn/2007e.html#11 A way to speed up level 1 caches part of the above is old thread http://www.garlic.com/~lynn/2006p.html#10 What part of z/OS is the OS? http://www.garlic.com/~lynn/2006p.html#11 What part of z/OS is the OS? http://www.garlic.com/~lynn/2006p.html#19 What part of z/OS is the OS? http://www.garlic.com/~lynn/2006p.html#27 What part of z/OS is the OS? ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
