calibre-parallel process uses large amount of Win32 Handles

[CheriePie]

While doing it's background downloading thing, Calibri launches some process called calibre-parallel. After this process launched on my system, and begun doing it's thing, it immediately chewed up 53,210 Win32 Handles!

I was able to quit that particular process, while the main part of calibre remained running, and my Win32 Handles went back down to normal.

I'm not sure exactly what that process is used for, downloading or fetching news I think. My system is a XPS M1730 2.4GHz Intel Core2 Duo with 2GB RAM running WinXP Pro SP3.


I also filed this as a ticket on the web site, only because I couldn't decide which way to do it. I thought that here anyone else could experiencing something similar could pipe up with suggestions, whereas I saw it more of a bug so I also thought it should go in the ticket system. Since I couldn't decide for sure, you're getting both.

[itimpi]

The calibre-parallel process is used for background tasks such as fetching articles, sending books to the reader or (probably most important) converting books to another format. The process will be re-started any time calibre is asked to perform this type of action.

Whether it should open so many handles I have no idea - it depends I guess on what type of handle they are and the complexity of the processing being performed.

[CheriePie]

Yeah, I figured out what it was used for. And I've successfully updated News and sent it to my Kindle 2 using this process. However, when it's done, it doesn't free up the handles, leaving the system in a somewhat unstable state if another app were to come along that needed lots of handles as well. In order to run "clean", an application really should clean up after itself. Instead, I'm left with 2 open calibre-parallel processes long after they're no longer needed, and they haven't freed up all the handles they used either.

[kovidgoyal]

Umm handles are just integers and IIRC your system if its 32 bit has about 2**32 = 4294967296 available, so i wouldn't worry about it if I were you

[CheriePie]

Alright, I won't worry about it.

But just so you know, I come from a software development environment and the devs always wanted to know about win32 handles and file handles and if they weren't cleaned up after each process and stuff like that. So it was always the kind of thing I reported. I'm not a software developer myself, but a network and system administrator, but the companies I've worked for have all been big names in software.

But your right, the normal user probably wouldn't notice it, though it certainly makes me not want to leave calibre running all the time since it doesn't shut down those extra processes after. And you'd kinda implemented that taskbar feature so people could leave it running. (Don't ask me why... I'm just wicked OCD about my system. :lol: )

Maybe these ones are just references and aren't as big of a deal as open file handles though so I won't fret it. And I'll zip it now since it doesn't seem to be an issue for anyone.

[kovidgoyal]

calibre delibrately leaves the process running, this is because in common with all python programs startup time for calibre is a problem. By leaving the processes running, when you run multiple tasks each processes can be re-used quickly.