Bug 1304455

Summary: Do not use lttng in rados/rbd by default
Product: [Red Hat Storage] Red Hat Ceph Storage Reporter: Tanay Ganguly <tganguly>
Component: RBDAssignee: Boris Ranto <branto>
Status: CLOSED ERRATA QA Contact: ceph-qe-bugs <ceph-qe-bugs>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 1.3.2CC: branto, ceph-eng-bugs, jdillama, kdreyer, kurs, mlawrenc, vakulkar
Target Milestone: rc   
Target Release: 1.3.2   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: RHEL: ceph-0.94.5-7.el7cp Ubuntu: ceph_0.94.5-5redhat1trusty Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2016-02-29 14:46:05 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Tanay Ganguly 2016-02-03 16:34:51 UTC 
Description of problem:
Continuously getting the Error message in vm.log file from qemu/kvm

libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886) 

Version-Release number of selected component (if applicable):
rpm -qa |grep ceph
ceph-common-0.94.5-4.el7cp.x86_64
ceph-osd-0.94.5-4.el7cp.x86_64
ceph-0.94.5-4.el7cp.x86_64
ceph-radosgw-0.94.5-4.el7cp.x86_64
ceph-debuginfo-0.94.5-4.el7cp.x86_64
ceph-selinux-0.94.5-4.el7cp.x86_64

selinux:
Loaded policy name:             targeted

How reproducible:
Always

Steps to Reproduce:
1. Create a RBD image, take snap and clone it.
2. Attach the same image in Qemu.
3. Create a VM on top of that RBD clone image.
4. Do some write operations of that image.

Actual results:
Seeing lots of Error in log message of the VM

Expected results:
There should not be any Error log message.

Additional info:


libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
Comment 2 Boris Ranto 2016-02-03 16:44:12 UTC 
We need to backport the following upstream PR (or rebase to 0.94.6):

https://github.com/ceph/ceph/pull/6415
Comment 3 Ken Dreyer (Red Hat) 2016-02-03 18:30:10 UTC 
Boris is right, we need https://github.com/ceph/ceph/pull/6415
Comment 4 Boris Ranto 2016-02-03 20:50:38 UTC 
dist-git commits related to build ceph-0.94.5-6.el7cp:
http://pkgs.devel.redhat.com/cgit/rpms/ceph/commit/?h=ceph-1.3-rhel-7&id=d81b7992d9797fd5138256828875a93c40400d3a
Comment 5 Boris Ranto 2016-02-03 22:02:45 UTC 
The package was successfully built in brew:

https://brewweb.devel.redhat.com/taskinfo?taskID=10437793
Comment 6 Ken Dreyer (Red Hat) 2016-02-03 22:50:25 UTC 
Needs adjustment to remove this conditional:

# LTTng-UST enabled on Fedora, RHEL 6, and SLES 12
%if 0%{?fedora} || 0%{?rhel} == 6 || 0%{?suse_version} == 1315
%global _with_lttng 1
%endif

The reason that upstream has this code is because lttng is not in EPEL 7. lttng is present in Red Hat Ceph Storage.
Comment 7 Boris Ranto 2016-02-03 22:51:45 UTC 
dist-git commits related to build ceph-0.94.5-7.el7cp:
http://pkgs.devel.redhat.com/cgit/rpms/ceph/commit/?h=ceph-1.3-rhel-7&id=c3392557e63a072b6a6cebbe2b9a0754c9dc561c
Comment 9 Tanay Ganguly 2016-02-08 08:53:02 UTC 
Marking it verified.

As i do not see any further error logs from my VM.log

libust[121880/121886]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:886)
Comment 11 errata-xmlrpc 2016-02-29 14:46:05 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2016:0313