<html>
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<div class="moz-cite-prefix">Phillip Hallam-Baker wrote on
11.12.2015 19:21:<br>
</div>
<blockquote
cite="mid:CAMm+LwiFd8TF8vMPgFu2+zwZaSRiL-S5f69OEpr0+BEqnpfZ3w@mail.gmail.com"
type="cite">
<meta http-equiv="Context-Type" content="text/html; charset=UTF-8">
<div dir="ltr">The IMAP protocol is slow because it is poorly
designed. It is single threaded with every transaction requiring
a separate request/response. So one big file causes everything
to jam up. Sorting of messages takes place in the client and the
changes are uploaded back to the server.
<div><br>
</div>
<div>Gmail also optimizes the user experience by separating out
metadata downloads from content and message data from
attachments. Their protocol is S/MIME aware while IMAP is not.</div>
<div><br>
</div>
<div><br>
</div>
<div>These are all fixable.</div>
</div>
</blockquote>
<br>
I'd like to correct some mis-information above.<br>
<br>
<ol>
<li>Thunderbird's IMAP implementation is multi-threaded. (In fact,
it's pretty much the only multi-threaded thing in all of TB, if
I remember correctly.)</li>
<li>The protocol itself is asynchronous. You can issue several
commands at (almost) the same time, and the second can finish
before the first. This is basically the same concept that
node.js follows, which is very fast and modern. IMAP had this 20
years ago, on a protocol level.<br>
(Thunderbird additionally uses one thread and connection per
folder. I don't remember whether TB uses the async nature of
IMAP very much.)</li>
<li>IMAP does separate metadata from content. For that purposes,
it parses email messages on the server, and can return the
headers of an email separately from the body, and the body
separate from the attachments. That, too, was very modern for
its time.</li>
<li>IMAP and Thunderbird are blazingly fast on my machine here.
The folder with my primary work project has currently about
15000 emails, and is sufficiently fast. QuickSearch in TB is
almost instant, it takes about 1s to search the whole folder for
a subject.<br>
(Admittedly, my IMAP server is on my local network. Maybe the
slowness you encounter might be attributed to a slow IMAP server
or a slow desktop machine?)</li>
</ol>
<br>
TB has serious problems, no doubt. But they are not those you
mentioned.<br>
</body>
</html>