[imp] disallow Dynamic View

[Brendan Oakley]

Hi Michael,

On Fri, Jan 18, 2013 at 2:52 PM, Michael M Slusarz wrote:
> Quoting Brendan Oakley <gentux2 at gmail.com>:
>
>> My guess is that the dynamic mode is simply designed for IMAP servers
>> with faster responses.
>
>
> This is simply an inaccurate statment.  There are LESS IMAP calls per page
> load in dynamic view than in basic view, since basic view has to recreate
> all sorts of state that, in dynamic view, can be cached.  Not to mention
> that basic view has to create the entire UI every time the user clicks a
> page (and may have to initialize other Horde applications, depending on
> menu/sidebar settings, which only adds to the load).  Dynamic view only
> requires simple tasks to be completed.

The web server load is not a problem in our environment, as we have
plenty of distributed web servers to handle the load.

> This is a *completely* different issue than saying "dynamic view is slow".
> This is a different use pattern of the UI.  It has nothing to do with the
> design/speed of the underlying code.

Sorry but I never said "dynamic view is slow."

> If this is unacceptable to you, disable and lock preview mode.

The only option I found for doing this applies to Basic mode and does
not work in Dynamic mode.

This is not about what I consider acceptable. In my testing this mode
does not work well in our current environment and therefore needs to
be disabled.

> But from a practical standpoint: unless/until you can fix the true problem
> of the "slowness" - the IMAP server - any solution (whether IMP or other
> software) is going to provide unacceptable performance.  (Without any sort
> of optimizations, preview AJAX requests should worst case scenario take
> 500-1000ms maximum.)

Then the dynamic mode is indeed designed for IMAP servers with faster
responses than ours.

The extra UI overhead of a complete page reload, as in the Basic view,
is actually desirable in this case. The user must decide what message
to open and purposely click on it. He cannot just hold down an arrow
key and fire off thousands of body fetches in a matter of a couple
seconds. This means less load on the IMAP server.

I agree, the IMAP backend needs to be changed, in any case.
Integrating Horde in our site is one step in the plan to make that
possible. Once the work is complete, of course allowing dynamic view
for our users will be desirable.

Thanks
Brendan