Johnny Tan wrote: > By default, z/VM minidisk cache is enable. As I know, z/VM minidisk cache is > using z/VM real memory and expanded storage. Would anyone recommend to use > minidisk cache on z/VM where the main purpose of z/VM here is to support > Linux guests? > > Today's DASD technology has fast write, which means that writing to DASD will > no longer write direct to the disk, however, it will write direct to the > cache (which is memory) of the DASD controller. In view of this fast write > feature, is minidisk cache still relevant? If it is still relevant, does the > z/VM minidisk cache work well to predict open system I/O characteristics in > view that I/O pattern of open system is random (not sequential) as compared > to MVS ?? Given that Linux has good disk caching built-in, mdc does only make sense for shared volumes. Deactivating mdc for those volumes that are local to either of your guests saves double caching. --
Carsten Otte IBM Linux technology center ARCH=s390 ---------------------------------------------------------------------- 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
