Liron Aravot has submitted this change and it was merged. Change subject: infra/storage: send commands to the SPM on a FIFO basis ...................................................................... infra/storage: send commands to the SPM on a FIFO basis The synchronized 'syncObj' object, used to serialize SPM commands from the manager to the hypervisor is not particularly fair, which makes these commands to arrive in random order on vdsm. This is particularly true when a lot of commands are sent to the manager, using the API for example. In this case, some delays may get very large. Using a fair ReentrentLock instead of executing the code in a synchronized block, respects the order of the commands, eliminating the chance of starvation. Using a reentrant lock makes it easy to report the number of threads waiting on the lock as well. Change-Id: I23fb85a4179c8a77bf1b3df532d43edc4207f33a Bug-Url: https://bugzilla.redhat.com/1277057 Bug-Url: https://bugzilla.redhat.com/1282764 Signed-off-by: Tim Speetjens <tim.speetjens(a)redhat.com&gt; --- M backend/manager/modules/vdsbroker/src/main/java/org/ovirt/engine/core/vdsbroker/irsbroker/IrsBrokerCommand.java M backend/manager/modules/vdsbroker/src/main/java/org/ovirt/engine/core/vdsbroker/irsbroker/IrsProxyData.java 2 files changed, 29 insertions(+), 13 deletions(-) Approvals: Tal Nisan: Looks good to me, approved Liron Aravot: Verified; Passed CI tests -- To view, visit https://gerrit.ovirt.org/48245 To unsubscribe, visit https://gerrit.ovirt.org/settings Gerrit-MessageType: merged Gerrit-Change-Id: I23fb85a4179c8a77bf1b3df532d43edc4207f33a Gerrit-PatchSet: 9 Gerrit-Project: ovirt-engine Gerrit-Branch: master Gerrit-Owner: Tim Speetjens <tim.speetjens(a)redhat.com&gt; Gerrit-Reviewer: Allon Mureinik <amureini(a)redhat.com&gt; Gerrit-Reviewer: Arik Hadas <ahadas(a)redhat.com&gt; Gerrit-Reviewer: Daniel Erez <derez(a)redhat.com&gt; Gerrit-Reviewer: Jenkins CI Gerrit-Reviewer: Liron Aravot <laravot(a)redhat.com&gt; Gerrit-Reviewer: Maor Lipchuk <mlipchuk(a)redhat.com&gt; Gerrit-Reviewer: Moti Asayag <masayag(a)redhat.com&gt; Gerrit-Reviewer: Piotr Kliczewski <piotr.kliczewski(a)gmail.com&gt; Gerrit-Reviewer: Roy Golan <rgolan(a)redhat.com&gt; Gerrit-Reviewer: Tal Nisan <tnisan(a)redhat.com&gt; Gerrit-Reviewer: Tim Speetjens <tim.speetjens(a)redhat.com&gt; Gerrit-Reviewer: gerrit-hooks <automation(a)ovirt.org&gt;