Re: [Libvir] Make python binding release GIL when using threads

On Fri, Oct 06, 2006 at 01:10:18AM +0100, Daniel P. Berrange wrote: > In the virt-manager app I'm using the python bindings to libvirt for all > operations. For long running operations such as creating new domains, or > saving/restoring domains I fork a background thread to do the call, so that > the main UI / status refresh can carry on working. Except this wasn't working. > The main thread was being blocked for the entire duration of the background > thread. After a lot of nasty debug sessions I discovered that the main > thread was being blocked in the GTK event loop attempting to aquire the > Python GIL (Global Interpreter Lock). The only way this could be occurring > is if the background thread doing the libvirt call held the GIL. > > And indeed after looking at the source for the libvirt python bindings it > appears we never release the GIL when calling into the libvirt C apis, so > for the entire duration of virDomainCreateLinux the python interpreter > is completely stopped. Clearly this sucks because virDomainCreateLinux > can take a very long time. Okay, true. Simply that I never had to deal with something similar in the past so I never looked into this before.

> > output.write("libvirt_begin_allow_threads;\n"); > 425a427 > > output.write("libvirt_end_allow_threads;\n"); I was wondering if it wasn't nicer to use functions rather than inlined macros. Maybe if kept as macro this should be turned to upper case to keep consistant with existing practice, but it's not a big deal.