RE: Tweaking FTP file transfers

I'm guessing the files on the 400 include trailing blanks in the database
fields. But when you transfer them to the WinTel box, you've converted them
to TAB or CSV format, and consequently trimmed off the trailing blanks. In
addition, the data's CCSID is probably already changed to PC ASCII on the
WinTel box.


-Bob Cozzi
www.RPGxTools.com
If everything is under control, you are going too slow.
- Mario Andretti


-----Original Message-----
From: web400-bounces@xxxxxxxxxxxx [mailto:web400-bounces@xxxxxxxxxxxx] On
Behalf Of Hayes, Joe
Sent: Thursday, August 04, 2005 11:28 AM
To: 'Web Enabling the AS400 / iSeries'
Subject: RE: [WEB400] Tweaking FTP file transfers

Based on your comments below, could there simply be paging issues because of
the inordinately large amount of memory being used?

 -----Original Message-----
From:   web400-bounces@xxxxxxxxxxxx [mailto:web400-bounces@xxxxxxxxxxxx]  On
Behalf Of web400@xxxxxxxxxxxxxxxx
Sent:   Wednesday, August 03, 2005 3:44 PM
To:     Web Enabling the AS400 / iSeries
Subject:        Re: [WEB400] Tweaking FTP file transfers


> We have a need to FTP several large files nightly to one of our vendors.
> These files are 350K and up and at times take hours to FTP from our 400 to
> the remote server yet if we place these files on a Wintel box, they'll FTP
> in minutes.

Hmmm... why would it matter whether they're coming from Windows or an 
iSeries?

Have you tested the connection between your iSeries and it's gateway to 
see if you receive packet loss?  A ping flood (during off-hours) might be 
a good test.

If your performance is that much worse than a Windows machine, I'd have to 
assume that there's a hardware problem -- or a gross misconfiguration.


> I'm wondering what on the AS/400 could be tweaked to improve the
> transmission time.  Two things I've been looking at are the TCP send and
> receive buffer sizes which are currently set to 1,000,000 (default value
is
> 8,192).

Although that's a colossal waste of memory, I don't see how it would cause 
slowdowns.  (You do understand that that isn't a system-wide setting, 
right?  It's a per-socket setting. If you have 1000 active sockets, you'll 
have 2gb of memory in use!)

> Also I've found some jobs lingering in QSYSWRK, QTFTPxxxxx which
> run at priority 25.  I could drop the class down to something equal to or
> lower than my interactive subsystem but I'm not quite sure what these jobs
> do and if changing their priority really would do anything.

Those are FTP server jobs.  I understood from your message that your 
iSeries was acting as a client, not a server. If that's the case, those 
jobs are completely irrelevant.

Like I said, I'd be looking for a hardware problem.  (Dropped packets, 
corrupted packets, bad cable) or I'd be looking for a misconfigured 
interface (MTU set too low, duplex set incorrectly, etc)