Thanks for asking, Carsten. I would expect, without samples to cite, that DCSS itself is often used, XIP less so.
In my own experience, the lack of interest in XIP follows lack of interest in shared R/O filesystems of any type. (XIP is technically just as easy to maintain, if less well understood, perhaps more difficult to set-up first time.) Since XIP was rolled into EXT2, surely there is little maintenance for Andrew to fuss about. Consistency helps: There should be shared memory on other virtualization platforms. (Apart from deduplication hacks.) DCSS itself could be thought of as another form of reserved memory, not something peculiar to S/390. Also, how does Android addresses flash memory life? It's not read only, but the less writing done the longer flash will last. So following that example, DCSS using JFFS2 might be interesting. (JFFS2 has its own issues with layering violations. Don't get me started.) Apart from Linux on System z, I continue to hear about read-only or write-less-often. Just this week, someone asked my local LUG for suggestions, wanting to know which filesystems drive R/W less fiercely with flash on USB. On Tue, Feb 12, 2013 at 4:36 AM, Carsten Otte <co...@de.ibm.com> wrote: > Dear Linux on z community, > > a few years ago we've introduced execute in place, which can be used to > save some memory by using z/VM DCSS segments. Since the size of > main memory for virtual servers has increased much faster than the size > of binary executables and libraries since, this technique has become less > attractive. Andrew Morton, the leading maintainer for the memory manager > in Linux, has raised the question if this is still needed. > > Who's using execute in place in their environment today? What are your > plans of future use? Can we discontinue the technology or shall we keep > it around? > > with kind regards > Carsten Otte > System z firmware development / Boeblingen lab > --- > Every revolution was first a thought in one man's mind; > and when the same thought occurs to another man, it is the key to that era. > > - Ralph Waldo Emerson, Essays: First Series, 1841 > > ---------------------------------------------------------------------- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > ---------------------------------------------------------------------- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ -- -- R; Rick Troth Velocity Software http://www.velocitysoftware.com/ ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
