To: perfctr-devel@lists.sourceforge.net Subject: perfctr-2.0-pre5 released perfctr-2.0-pre5 is now available at the usual place: . The reason I'm not calling this "2.0 final" is that I have two problem reports which I wanted to try to resolve first: - One user has observed extreme variations in final counts when using perfex to monitor an application on an SMP box; the same application has deterministic counts on a UP box. (perfctr-2.0-pre4, 2.4 kernel, 4-way Xeon SMP, Xeon UP) - Another user has reported kernel crashes when using perfctr together with "pvfs" and Myrinet "gm" drivers. Perfctr works fine if run without pvfs/gm, and pvfs/gm work fine if run without perfctr. It looks as if pvfs/gm clobbers the current process' "perfctr" pointer, although we haven't yet been able to confirm this or explain why it happens. (perfctr-1.6-update-1, 2.2 kernel, cluster of P6 UP boxes) 2.0-pre5 has a CONFIG_PERFCTR_DEBUG option to enable some internal consistency checks which I hope will help debug the above-mentioned problems. I will make a perfctr-1.6-update-2 release later this week with the debug option added and new patches for recent 2.4 kernels. Version 2.0-pre5, 2001-05-11 - Structure layout changes to reduce sampling overheads. The ABI changed slightly, but I hope this is the last such change for some time. - Fixed two bugs related to the interaction of interrupt-mode perfctrs and the lazy EVNTSEL MSR update cache in the low-level driver. (Interrupt-mode support is still disabled in the high-level drivers, however.) - Fixed a bug in examples/perfex where it forgot to initialise the pmc_map[] control field. This caused the driver to refuse attempts to use more than one counter. The current fix is for P6/K7 only; a general "fixup" procedure will be added to the user-space library later. - Added a CONFIG_PERFCTR_DEBUG option to enable some internal consistency checking in the driver. This is a temporary measure intended to help debug two open problem reports. / Mikael Pettersson