On Mon, Jul 11, 2011 at 3:07 PM, Jason Woofenden <jason@jasonwoof.com> wrote:
> notmuch search tag:foo is slow!
>
> (when my e-mail files are not already in the disk cache)
>
> I saw on my activity monitor applet that it was using mostly i/o,
> and started to wonder if it was opening every e-mail. I little work
> with strace and searching revealed that this command was opening
> many many e-mail files from my maildir(s). I spent a little while
> digging around in the notmuch source, and didn't see where it was
> opening the email files.

It is opening every file to get a few headers to display in the search
output.  Istvan Marko sent an experimental patch to store these
headers in the database a while ago, though as far as I know there
hasn't been any progress cleaning it up for inclusion:
id:"m3sjsv2kw2.fsf@zsu.kismala.com" .