Bryan J. Smith b.j.smith@ieee.org wrote:
Pre-i686 (PPro-P4, K6/Athlon, Cyrix M2/C3, WinChip2?) architectures take issue some applications. E.g., Red Hat, among other distros, have not bothered with pre-i686 NPTL support. There are better distros for i486 (K5, Cyrix Mx/M1, WinChip) or i586 (exactly Pentium-only) architectures than anything Fedora Core based (RHEL), SuSE Linux based (SLES/NOES), Mandrake Linux or similarly based.
This was true for Fedora Core 2, and only handfull of packages were affected with the problem. The problem was that db libraries were compiled with NPTL, and some programs linked against the db library failed to work correctly because of that (cyrus-imapd seems to be the most problematic one).
The Apache web server was not affected by this problem, at least not in simple/default configuration.
The i386 glibc package on Core 3 should have NPTL support (it isn't i386 clean anymore, since for NPTL support it needs to include at least i486 instructions, however it is still labeled as i386 for some reason). If this updated glibc package is part of RHEL4, than everything should work correctly on i586 machines.
Since the kernel is the only i586/i686 package in RHEL4 , and the rest of the system uses i386 instructions (apart from glibc that uses i486 to implement NPTL, if they did same hack as on FC3), the distribution should work on i486 too with custom compiled kernel.