On Wed, Nov 23, 2011 at 12:37 PM, Pawel Sawicki <[email protected]> wrote: > Hi All, > > We are running Firebird-2.5.1 on virtual machine with RHEL6.0. Our > hypervisor is KVM. From time to time we get Firebird unresponsive and we > need to restart it. This situation occurs on heavy loaded system, strace > shows that the problem is related with the fragment of code which contains > invocation of pthread_cond_timedwait sytem call (file > /src/jrd/isc_sync.cpp). It looks like all threads lost completely > synchronization and block each other. We use your standard distribution > package. There is small chance that this problem can be attributed to > different environment used during build, thus we are going to recompile > Firebird from scratch. Hovewer more viable explanation is that we > encountered bug which becomes visible in virtual environment. We have some > experiances with timekeeping in virtual machines which is not very accurate > and could possibly lead to this effect. > If pthread_cond_timedwait sytem is not working correctly can it be simply > replaced by other system call which could be more reliable ? Could you show what is the time source , it is possible to have a unstable clock source
cat /sys/devices/system/clocksource/clocksource0/current_clocksource kvm-clock dmesg | grep kvm-clock [ 0.000000] kvm-clock: cpu 0, msr 0:7a8381, boot clock [ 0.000000] kvm-clock: cpu 0, msr 0:101d381, primary cpu clock [ 0.004000] kvm-clock: cpu 1, msr 0:102d381, secondary cpu clock ntp should be disabled on the guest but enabled on the host > > Best regards > > Pawel > > -- > View this message in context: > http://firebird.1100200.n4.nabble.com/Running-Firebird-on-KVM-tp4099137p4099137.html > Sent from the firebird-devel mailing list archive at Nabble.com. > > ------------------------------------------------------------------------------ > All the data continuously generated in your IT infrastructure > contains a definitive record of customers, application performance, > security threats, fraudulent activity, and more. Splunk takes this > data and makes sense of it. IT sense. And common sense. > http://p.sf.net/sfu/splunk-novd2d > Firebird-Devel mailing list, web interface at > https://lists.sourceforge.net/lists/listinfo/firebird-devel ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-novd2d Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
