Re: [naviserver-devel] Upload Progress

[Zoran V. <zv...@ar...>]

Am 02.01.2006 um 21:13 schrieb Stephen Deasey:

>
> If the problem is that threads are too "heavy", then it's pointless to
> use aio_write() etc. if the underlying implementation also uses
> threads.  It will be worse than using conn threads alone, as there
> will be extra context switches as control bounces from driver thread,
> to IO thread, back to driver thread, and finally to conn thread.

Well, I really do not know which OS uses what implementation.
We now know thaat Linux uses userland threads.
I do not know about Darwin but I can peek into their sources.
Same for Solaris.

>
> Here's another way to look at it:  We already dedicate a conn thread
> for every download.  What's so special about uploads that we can't
> also dedicate a thread to them? The threads are long lived, you can
> prevent them from running Tcl etc...

This is true. What I had in mind was to make it simple as possible
by reusing already present driver thread w/o making it more complex
than needed by adding even more theads. We already have lots of
them anyways.

>
> Sure, the ideal would be AIO for both uploads and downloads.  But the
> io_* API is busted, at least on one major platform, possibly more.
> Have you looked at Darwin, how do they implement it?  What are you
> going to do on Windows?
>

I do not know. On windows most of the things  are already async
(WaitForMultipleObjects) so I believe that we can work-arround by
adding our own wrapper for AIO as we have done for mmap.

But this is all speculation. I never went farther than reading
man pages and contemplating about it. Vlad went considerably
farther and have tried couple of things.

I believe it is the time we have to make ourselves pretty clear
what are we about to do:

   o. add upload statistics and control?
   o. improve upload altogether
   o. redesign upload altogether

At the moment, most visible/needed improvement coud/would be
a sort of upload statistics, as we do miss this functionality.

Zoran

>
> -------------------------------------------------------
> This SF.net email is sponsored by: Splunk Inc. Do you grep through =20
> log files
> for problems?  Stop!  Download the new AJAX search engine that makes
> searching your log files as easy as surfing the  web.  DOWNLOAD =20
> SPLUNK!
> http://ads.osdn.com/?ad_idv37&alloc_id=16865&op=3Dclick
> _______________________________________________
> naviserver-devel mailing list
> nav...@li...
> https://lists.sourceforge.net/lists/listinfo/naviserver-devel