Which OSs and SAPI should PHP 5.6 support?

By way of a background. I've been doing a review of the exting code base looking at how to establishing a roadmap extend OPcache functionality across all supported OSes and SAPIs. And this raises a supplementary Q: which OSs and SAPIs should we be supporting for PHP 5.6 anyway? I would be interested in the views of the dev team on this. It would be good to agree a list of which OSs are to be supported at PHP 5.6, which SAPIs are supported, and a matrix of which SAPIs are supported on non-threaded and build TSRM variants. Examples of what I am talking about are SAPIs with no clear evidence of active support (I've listed the last non-bulk change in brackets to give a measure of the level of support):

    aolserver (2008), caudium (2005), continuity (2004), nsapi (2011),
    phttpd (2002), pi3web (2003), roxon (2002), thttpd (2002),
    tux (2007), webjames (2006)
I realise that some of these may still be actively used with a user community out there wanting to track current versions, and this is just a case of "if ain't broke..."  However, I do wonder when some of these were actively maintained and routinely tested against the current versions at release -- and if not then perhaps PHP 5.6 is the correct point to retire them from the source tarball and configure options?

Likewise in the Zend, TSRM, ext/opcache ... sources, there is conditional code dependent on BeOS, __sgi, __osf__, __IRIX__, NSAPI, PI3WEB, GNUPTH(*), OS_VXWORKS, etc. as well as obsolete BSD versions -- OSs that are no longer actively supported. Again I ask the Q how and when are these tested and if not then shouldn't we retire this support? Part of my reasons for asking this is work in preparation for OPcache issue #118 -- Transparent SHM reuse. Doing this with robustly with good performance characteristics -- for *all* currently referenced OSs -- is a pain. Reviewing a range of other best-of breed packages which use shared SMA-based resources, it seems to me that the memcached approach is the cleanest: it uses the POSIX APIs and supports any OSes which support these APIs. If we limited TSRM and OPcache support at PHP 5.6 to two code variants, POSIX + WIN32, surely this would still cover all the major supported OSes? //Terry Ellison (*) GNU threads is still supported but it prevents utilisation of SMP systems and there is a minimal performance differences from POSIX threads on a single processor system.