At present, RHEL 4 fullvirt guests have no disk stats visible in the RHEL 5 host. RHEL 4 guests with PV drivers have the correct /sys/devices/xen-backend/.../statistics/* files, but they always contain zeroes. Notes: (1) I'm not sure yet if these two things are the same issue or separate bugs - I may split this bug into two parts later. (2) This BZ may need kernel & libvirt (& hypervisor & PV driver??) sub-bugs in future in order to get all the work done.
Kernel part of this is covered by bug 250104. Userspace (libvirt) part is covered by bug 306931.
Userspace (libvirt) part is included as part of the rebase on update 2, this would still need QA (checking the device paths are correct in U3) before marking this as fixed once the kernel part is done, Daniel
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
# virsh domblkstat rhel4.7_x86_64_hvm_guest /dev/xvdb /dev/xvdb rd_req 1 /dev/xvdb rd_bytes 4096 /dev/xvdb wr_req 0 /dev/xvdb wr_bytes 0 /dev/xvdb errs 0 # virsh domblkstat rhel4.7_x86_64_hvm_guest /dev/xvdf /dev/xvdf rd_req 9 /dev/xvdf rd_bytes 75776 /dev/xvdf wr_req 2987 /dev/xvdf wr_bytes 50900992 /dev/xvdf errs 0 I am not sure if this was intentional or not but, this is working for rhel3 pv-on-hvm guests as well: # virsh domblkstat rhel3.9_x86_64_hvm_guest /dev/xvda /dev/xvda rd_req 1 /dev/xvda rd_bytes 4096 /dev/xvda wr_req 0 /dev/xvda wr_bytes 0 /dev/xvda errs 0 # virsh domblkstat rhel3.9_x86_64_hvm_guest /dev/xvdb /dev/xvdb rd_req 2 /dev/xvdb rd_bytes 5120 /dev/xvdb wr_req 1141 /dev/xvdb wr_bytes 50630656 /dev/xvdb errs 0
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2009-0142.html