Re: Slowdown

[John Goerzen <jgoerzen@xxxxxxxxxxxx>]

On Tuesday 12 February 2008 5:33:31 pm Aaron Kaplan wrote:
> On Wed, 9 Jan 2008 16:52:38 -0600, "John Goerzen"
>
> <jgoerzen@xxxxxxxxxxxx> said:
> > I might suggest you grab the darcs tree and try unapplying a few
> > patches, and
> > see what happens.
>
> The slowdown appears to be related to the removal of the local version
> of imaplib.py.  This threw me for a loop for a while: I unpulled big

Ugh.  Unfortunately, that's almost the worst possible news, because 
imaplib.py is *huge*.  I'm going to grasp at straws here to suggest where 
you might start on this.  I guess the first thing to do is figure out if an 
OfflineIMAP patch made the change, or an upstream change made the 
difference.

You could look at the darcs history for imaplib.py from the time I imported 
2.52 until the time we got rid of it. You might try the unmodified 2.52 
imaplib.py with the current code and see if it is any better.  If it is, 
that would point the bloody finger squarely at the Python maintainers.  If 
it's not, that means one of the OfflineIMAP patches boosted performance.  
Then at that point, it's a matter of figuring out which one, and seeing if 
we can get it sent upstream.  I do not want to reintroduce imaplib.py to the 
source tree.

-- John

> bunches of patches until I got to a version that was fast, then I
> started pulling patches back in, to see where it would get slow again,
> but I pulled all the way back up to the current version and the slowdown
> didn't reappear!  This turned out to be because after I pulled the patch
> "Remove local imaplib.py", the local imaplib.py was gone, but the local
> imaplib.pyc that had been compiled from it was still there.  Once I
> deleted that, it got slow again.
>
> I did my testing on a single folder with 1500 messages, and it takes 12
> seconds with the current version vs. 7 seconds for the old version.
> /usr/lib/python2.5/imaplib.py on my system says it's version 2.58; the
> last version included with offlineimap says version 2.52.
>
> -Aaron