Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: "Frank Millman" <frank@chagford.com>
Newsgroups: comp.lang.python
Subject: Re: Question about asyncio and blocking operations
Date: Fri, 29 Jan 2016 07:23:21 +0200
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"Ian Kelly"  wrote in message 
news:CALwzidn6NfT_O0cfHw1itWja81+MW3scHuEcADVCen3ix6z73w@mail.gmail.com...
>
> As I commented in my previous message, asyncio.Queue is not
> thread-safe, so it's very important that the put calls here be done on
> the event loop thread using event_loop.call_soon_threadsafe. This
> could be the cause of the strange behavior you're seeing in getting
> the results.
>

Using call_soon_threadsafe makes all the difference. The rows are now 
retrieved instantly.

I have read the other messages, and I can see that there are some clever 
ideas there. However, having found something that seems to work and that I 
feel comfortable with, I plan to run with this for the time being.

Thanks to all for the very stimulating discussion.

Frank