* Urs Beyerle ([log in to unmask]) [20061115 11:13]: > As written in > ftp://ftp.scientificlinux.org/linux/scientific/44/i386/contrib/RPMS/xfs/README, > XFS is not recommended on SL4 32bit kernels. Correct. > What kind of problems where observed? Starting with RHEL4, the 4KSTACKS option is enabled when the kernel is compiled. This limits each process' kernel stack to 4K with separate stack for interrupts. XFS can have deep call chains (it's a complex filesystem doing complex stuff) and the codebase included in SL4 has not been updated to take this reduced stackspace into consideration (it's effectively the XFS codebase from the 2.6.9 times). As a result, it is possible to load the machine so that XFS overflows its stack and then the game is over. It can be easily triggered by stacking several software layers (SCSI+LVM/MD+XFS+NFS) on top of each other but it has been demonstrated that the stack overflow can be triggered with sufficient load on plain SCSI+XFS systems as well. > Is somebody working on a solution, which does not require to > recompile the standard SL4 kernel? The proper solution would be to backport stack-usage reducing XFS patches from newer vanilla kernels to the SL4 kernel. AFAICT nobody is working on it actively as we speak. There are some garage projects here and there (hint-hint ;) but no ETA and certainly no commitment. Your best bet is to move to 64-bit platform (practically any CPU you can buy nowadays would qualify). Peter -- .+'''+. .+'''+. .+'''+. .+'''+. .+'' Kelemen Péter / \ / \ [log in to unmask] .+' `+...+' `+...+' `+...+' `+...+'