On 12/7/11, Thomas Himmelmann <[email protected]> wrote: > Unionfs 2.5.10 don't work stable on kernel 3.0 and 3.1 for me.
2.5.10 is rock-solid with a 3.0.7 kernel for me. There is something that I found out about the Linux kernel, that might affect the stability of Unionfs... A little while ago, we found that one of these config option makes operation unreliable: CONFIG_SCHED_SMT SMT scheduler support improves the CPU scheduler's decision making when dealing with Intel Pentium 4 chips with HyperThreading at a cost of slightly increased overhead in some places. If unsure say N here. CONFIG_SCHED_MC Multi-core scheduler support improves the CPU scheduler's decision making when dealing with multi-core CPU chips at a cost of slightly increased overhead in some places. If unsure say N here. We were getting mysterious errors when using the 'cp' command. When copying a complete directory hierarchy, some files/directories were sometimes completely missing from the destination. There were no error messages. This has nothing to do with Unionfs (these errors were occurring in ext2/3 partitions outside of any layer filesystem), I am describing a fundamental flakyness of the kernel, not just the 3.x, earlier too. I discovered that turning off CONFIG_SCHED_SMT and CONFIG_SCHED_MC fixed it. It is probably only one of those that is the culprit though, probably CONFIG_SCHED_MC, but I never verified that. So, my kernel has: CONFIG_SMP=y # CONFIG_SCHED_SMT is not set # CONFIG_SCHED_MC is not set I recommend, configure your kernel the same, then see if you still get the problems with Unionfs 2.5.10. Regards, Barry Kauler _______________________________________________ unionfs mailing list: http://unionfs.filesystems.org/ [email protected] http://www.fsl.cs.sunysb.edu/mailman/listinfo/unionfs
