Re: [python-win32] Dispatch command hangs
Yeah that's exactly it, there's a separate application running that is delivering COM objects to my python script. Each object is its own callback which requires a Dispatch call to get access to the properties. This can be several thousand in a very short period of time and while this happens my other thread will attempt to create a COM object and seems to hang on the Dispatch call. During very high loads, the 2nd thread that is trying to create a new object can hang for almost a minute. On Thu, Aug 15, 2019 at 10:21 PM Tim Roberts wrote: > On Aug 15, 2019, at 9:28 PM, Joel Gross wrote: > > > > Yeah I'm calling CoInitialize. I can give CoInitializeEx a shot, but > there's no clear-cut way to set a priority for Dispatch? I'm not sure how > these objects are handled internally, is it just a regular queue? > > Is this an out-of-process server, so you’re receiving requests from other > processes? If so, then I think you’re seeing RPC (Remote Procedure Call), > which marshals the parameters back and forth, and I believe those are all > first-come first-served. > — > Tim Roberts, t...@probo.com > Providenza & Boekelheide, Inc. > > ___ > python-win32 mailing list > python-win32@python.org > https://mail.python.org/mailman/listinfo/python-win32 > ___ python-win32 mailing list python-win32@python.org https://mail.python.org/mailman/listinfo/python-win32
Re: [python-win32] Dispatch command hangs
On Aug 15, 2019, at 9:28 PM, Joel Gross wrote: > > Yeah I'm calling CoInitialize. I can give CoInitializeEx a shot, but there's > no clear-cut way to set a priority for Dispatch? I'm not sure how these > objects are handled internally, is it just a regular queue? Is this an out-of-process server, so you’re receiving requests from other processes? If so, then I think you’re seeing RPC (Remote Procedure Call), which marshals the parameters back and forth, and I believe those are all first-come first-served. — Tim Roberts, t...@probo.com Providenza & Boekelheide, Inc. ___ python-win32 mailing list python-win32@python.org https://mail.python.org/mailman/listinfo/python-win32
Re: [python-win32] Dispatch command hangs
Yeah I'm calling CoInitialize. I can give CoInitializeEx a shot, but there's no clear-cut way to set a priority for Dispatch? I'm not sure how these objects are handled internally, is it just a regular queue? Thanks On Thu, Aug 15, 2019 at 8:00 PM Tim Roberts wrote: > On Aug 14, 2019, at 6:12 PM, Joel Gross wrote: > > I have a multi-threaded application that receives a large number of > messages (COM objects) in sudden bursts. During this time, I've noticed > that if my other thread attempts to create a new COM object via the > Dispatch call, that call seems to hang until the messages have been > processed. This can take more than a minute sometimes. > > I am wondering if this is because the win32 side of things is still trying > to churn through all the messages? Is there a way to preempt this behavior > to ensure that the object I'm trying to create gets created immediately? > > This is a complicated topic. Are you calling CoInitialize? By default, > that will create a “single-threaded apartment”, where actions get handled > by a single thread. You can try calling CoInitializeEx with > COINIT_MULTITHREADED and see if that helps. > > But even then, you bang up against the Python interpreter lock, which only > allows the interpreter to handle one thread at a time. I wouldn’t think > you’d have to wait for the whole set of object requests to drain, but > threading in Python is always tricky. > — > Tim Roberts, t...@probo.com > Providenza & Boekelheide, Inc. > > ___ > python-win32 mailing list > python-win32@python.org > https://mail.python.org/mailman/listinfo/python-win32 > ___ python-win32 mailing list python-win32@python.org https://mail.python.org/mailman/listinfo/python-win32
Re: [python-win32] Dispatch command hangs
On Aug 14, 2019, at 6:12 PM, Joel Gross wrote: > I have a multi-threaded application that receives a large number of messages > (COM objects) in sudden bursts. During this time, I've noticed that if my > other thread attempts to create a new COM object via the Dispatch call, that > call seems to hang until the messages have been processed. This can take more > than a minute sometimes. > I am wondering if this is because the win32 side of things is still trying to > churn through all the messages? Is there a way to preempt this behavior to > ensure that the object I'm trying to create gets created immediately? > This is a complicated topic. Are you calling CoInitialize? By default, that will create a “single-threaded apartment”, where actions get handled by a single thread. You can try calling CoInitializeEx with COINIT_MULTITHREADED and see if that helps. But even then, you bang up against the Python interpreter lock, which only allows the interpreter to handle one thread at a time. I wouldn’t think you’d have to wait for the whole set of object requests to drain, but threading in Python is always tricky. — Tim Roberts, t...@probo.com Providenza & Boekelheide, Inc. ___ python-win32 mailing list python-win32@python.org https://mail.python.org/mailman/listinfo/python-win32
