> Message: 9 > Date: Thu, 28 May 2015 17:47:54 +0200 (CEST) > From: Dietmar Maurer <diet...@proxmox.com> > To: Stanislav German-Evtushenko <ginerm...@gmail.com> > Cc: pve-devel <pve-devel@pve.proxmox.com> > Subject: Re: [pve-devel] Default cache mode for VM hard drives > Message-ID: > <851217848.227.1432828074143.javamail.open-xcha...@ronja.mits.lan> > Content-Type: text/plain; charset=UTF-8 > >> > But there is currently only one io-thread in qemu, so this >> > cannot happen with qemu if above is the only problem? >> >> But there are other threads, right? Buffer can be changed by another >> thread where guest OS itself is running. > > No, AFAIK there is only one thread doing all IO (currently). But it > is using async IO with coroutines - maybe that can also trigger the > problem? >
Please have a look: root@virt1:~# for pid in $(pidof kvm); do echo "threads of $pid $(ps -o nlwp $pid | tail -1)"; done threads of 900883 6 threads of 606008 5 threads of 524867 4 threads of 524750 5 threads of 524550 7 threads of 521471 8 threads of 520324 4 threads of 519520 3 threads of 518997 4 threads of 152071 4 threads of 9029 3 threads of 8874 4 threads of 8695 3 threads of 8471 3 root@virt1:~# for pid in $(pidof kvm); do echo "threads of $pid $(ps -o nlwp $pid | tail -1)"; done threads of 900883 6 threads of 606008 5 threads of 524867 4 threads of 524750 5 threads of 524550 7 threads of 521471 5 threads of 520324 4 threads of 519520 3 threads of 518997 3 threads of 152071 4 threads of 9029 4 threads of 8874 3 threads of 8695 3 threads of 8471 3 Each kvm process have multiple threads and the number of them is changing in time. Stanislav _______________________________________________ pve-devel mailing list pve-devel@pve.proxmox.com http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
