Re: how to set network io priority for a process?
On Wed, 01 Aug 2007, Douglas Allan Tutty wrote:
> > I used analog async ITU-T V42 modems for a *long* time (fortunately, I was
> > able to move away before V9x hit the market). You really want an error-free
> > channel without compression for regular Internet over PPP domestic use, and
> > any modem still on the market should be able to deliver that to you just
> > fine. Just configure it for error correction without compression, and have
> > a proper error-free short and well-shielded serial connection to it if it is
> > an external modem.
>
> Its an external 3Com Courier modem, that's not the problem. I don't
That's the very best async modem ever produced, AFAIK. Especially if you
managed to get the latest firmware into it before 3com went to become
another useless outlet for stuff designed by others.
> know _where_ the errors happen, but the more times the download is
> interrupted the more frequently there are issues somewhere in the iso.
It is probably not being restarted properly, and some crap is left in the
file. One way you can get rid of that problem is to truncate the file
throwing away the last 1MB of it or so, for example (assuming this is not
one of those "multiple connections per file" transfers, in which case the
bogosity might be anywhere in the file).
If you DO get data errors with a Courier in error-correcting mode, it means
your serial cabling or serial port is bad, or that the other side is sending
you bad data.
And TCP protects data end-to-end against damage, so it can't be corrupted
that anyway, come to think of it.
> It has never been a problem when downloading packages via aptitude, even
> if I have to interrupt it. However, under sarge, I found that gftp
> would die out and not resume properly, corrupting the file, and that
> sometimes wget will also corrupt the file.
Try lftp. I know of no better ftp client. But it is command-line, which is
just as well: the transfer engine is well cared for, and not a secondary
thing to the GUI.
> For all I know, the errors are happening upstream of my ISP's modem.
Not on TCP connections. If it is ftp transfers that are being damaged when
the line is teared down, it is because your ftp client is broken.
--
"One disk to rule them all, One disk to find them. One disk to bring
them all and in the darkness grind them. In the Land of Redmond
where the shadows lie." -- The Silicon Valley Tarot
Henrique Holschuh
Reply to: