nnimap expiry seems very slow

[Lloyd Zusman <ljz@asfast.com>]

It seems that nnimap expiry is very slow for me.  During expiry, I
specify that the articles get moved to a "INBOX.<group>.saved" folder,
where <group> is the name of the nnimap group.

I have specified that this nnimap expiry takes place after a fixed
number of days.  The first time I leave an nnimap group after midnight,
this expiry takes place.  At this time, I get a series of messages like
this:

  nnimap: Marking article XXXX for deletion...

where XXXX is the message number.  It sometimes takes 5 seconds or
more per message number.

If I perform the same function interactively under mutt, these articles
get moved very quickly.  The way I do it in mutt is to mark a group of
articles, copy the marked articles to the .saved folder, delete the
marked articles, and then expunge all deleted articles.

I presume that gnus tries to do more or less the same thing, but like I
said, it takes ten times longer or more to perform this function under
gnus.

Before I dive in and do some serious debugging, can anyone think of some
sort of standard gnus setting that might be affecting the speed of this
expiry process?

Thanks in advance.

-- 
 Lloyd Zusman
 ljz@asfast.com