Re: [libvirt] virNetClientPtr leak in remote driver

2011/7/27 Matthias Bolte <matthias.bolte(a)googlemail.com&gt;: > doRemoteClose doesn't free the virNetClientPtr and this creates a > 260kb leak per remote connection. This happens because > virNetClientFree doesn't remove the last ref, because virNetClientNew > creates the virNetClientPtr with a refcount of 2. >

The memory leak I saw was due to virsh calling virEventRegisterDefaultImpl, but not calling virEventRunDefaultImpl. Because the event loop is initialized, the call to virNetSocketAddIOCallback in virNetClientNew succeeds. But virsh not driving the event loop results in not removing callbacks that were marked for deletion. Finally this leaks the virNetClientPtr using in the remote driver. I used a virsh -c qemu:///system to test. I was able fix this by calling virEventRunDefaultImpl after virConnectClose in virsh. But I don't think that this is the correct general solution.

To me the general problem seems to be the entanglement between the virNetClientPtr refcounting and the event loop. I'm not sure how to improve this in general. Maybe should have a thread calling virEventRunDefaultImpl as the comment on virEventRunDefaultImpl suggest.