Speed up printing?

Speed up printing?

Post by John Winte » Tue, 15 Jul 1997 04:00:00





Quote:>Hello,

>I've got a problem with my printer (a Toshiba PageLaser 12 model, it's approx.
>6 years old and emulates the HP LaserJet 500+ series). Almost anything I
>print is postscript and therefore converted to bitmap before printing (with
>the ghostscript ljetplus driver). The strange thing is the rather slow speed
>of printing. The transfer between my PC and the printer takes e.g. 8 minutes
>for 5 pages. Is it possible that the parallel line is so slow? After the
>printer has the page in its memory (2MB), it's only seconds until the page
>is printed - according to its documentation this model is capable of printing
>up to 12 pages per minute, therefore the link between PC and printer must be
>the bottleneck.

Not necessarily.  What sort of computer do you have?  Ghostscript can be
quite a CPU hog - it takes a significant amount of time to process some
pages on my P133.  Try running "top" whilst you're printing.

John
--
John Winters.  Wallingford, Oxon, England.

 
 
 

Speed up printing?

Post by Nils Philippse » Tue, 15 Jul 1997 04:00:00


Hello,

I've got a problem with my printer (a Toshiba PageLaser 12 model, it's approx.
6 years old and emulates the HP LaserJet 500+ series). Almost anything I
print is postscript and therefore converted to bitmap before printing (with
the ghostscript ljetplus driver). The strange thing is the rather slow speed
of printing. The transfer between my PC and the printer takes e.g. 8 minutes
for 5 pages. Is it possible that the parallel line is so slow? After the
printer has the page in its memory (2MB), it's only seconds until the page
is printed - according to its documentation this model is capable of printing
up to 12 pages per minute, therefore the link between PC and printer must be
the bottleneck.

Has anyone got a clue how to improve this? AFAIK the parallel port can be
much faster, e.g. with Laplink (DOS program to connect to PCs via the
parallel port) I saw transfer speed of approx. 160 KB/sec which would result
in a maximum of about 12 to 13 seconds for the whole printer's memory to
be filled.

Thanks in advance for any suggestions how to solve this.
Nils
--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


D 70197 Stuttgart                             Microsoft: They do it for money.

 
 
 

Speed up printing?

Post by JIM HICK » Tue, 15 Jul 1997 04:00:00


: Not necessarily.  What sort of computer do you have?  Ghostscript can be
: quite a CPU hog - it takes a significant amount of time to process some
: pages on my P133.  Try running "top" whilst you're printing.

and what is barely noticable delay on P133 is agony on a 386DX-40.

 
 
 

Speed up printing?

Post by Christopher B. Brow » Wed, 16 Jul 1997 04:00:00





>>I've got a problem with my printer (a Toshiba PageLaser 12 model, it's approx.
>>6 years old and emulates the HP LaserJet 500+ series). Almost anything I
>>print is postscript and therefore converted to bitmap before printing (with
>>the ghostscript ljetplus driver). The strange thing is the rather slow speed
>>of printing. The transfer between my PC and the printer takes e.g. 8 minutes
>>for 5 pages. Is it possible that the parallel line is so slow? After the
>>printer has the page in its memory (2MB), it's only seconds until the page
>>is printed - according to its documentation this model is capable of printing
>>up to 12 pages per minute, therefore the link between PC and printer must be
>>the bottleneck.
>Not necessarily.  What sort of computer do you have?  Ghostscript can be
>quite a CPU hog - it takes a significant amount of time to process some
>pages on my P133.  Try running "top" whilst you're printing.

The other significant question is whether there's enough RAM.

When I originally bought my HP5L, I had only 8MB of memory.  Rendering
for this 600DPI printer did not bring joy and happiness to the
system.

600x600 x 8 x 11 = about 4MB of memory

At 300 DPI, that's only 1MB, but if that moves things into swap space,
then performance will suffer rather terribly.

The speed of the parallel port shouldn't be a factor; I can get
several pages per minute out of my HP5L, which pumps out roughly 4
times as much data per page.

If we're talking about a 486DX/66, then that should be enough CPU to do
at least 2-3 pages per minute.  

- If there's 8MB of RAM or less on the system, that's a likely
bottleneck.  Without further information to go from, this is by far
the most likely cause of ill performance.

- If the CPU is less powerful than a 486DX/66, then that's a likely
bottleneck.  

- The parallel port is *conceivable,* but unlikely.  If it's the
problem, then there's something messed up with hardware.

I agree that "top" is likely to provide useful info; I'd speculate
that it will indicate that a couple megs of swap space are in use.
--

PGP Fingerprint: 10 5A 20 3C 39 5A D3 12  D9 54 26 22 FF 1F E9 16
URL: <http://www.hex.net/~cbbrowne/>
Q: What does the CE in Windows CE stand for?  A: Caveat Emptor...

 
 
 

Speed up printing?

Post by Nils Philippse » Wed, 16 Jul 1997 04:00:00


Well, I got a bunch of replies by mail as well as followups in the news,
I'll try to give excerpts of the replies and answers on questions therein.


--snip--

[del]

Quote:>is printed - according to its documentation this model is capable of printing
>up to 12 pages per minute, therefore the link between PC and printer must be
>the bottleneck.

Not necessarily.  What sort of computer do you have?  Ghostscript can be
quite a CPU hog - it takes a significant amount of time to process some
pages on my P133.  Try running "top" whilst you're printing.

John
--
John Winters.  Wallingford, Oxon, England.
--snap--

I split the process up into two parts, ghostscript rendering and actual
printing, just because I was curious about it. I used the famous tiger.ps,
that comes with ghostscript (/usr/share/ghostscript/4.03/examples/tiger.ps
or similar to this). The rendering took about 9 seconds and the transfer to
the printer took 3 minutes. The rendered PCL file was approx. 900KB in size,
so the transfer speed was at about 5KB/sec.


--snip--
[del]

The other significant question is whether there's enough RAM.

When I originally bought my HP5L, I had only 8MB of memory.  Rendering
for this 600DPI printer did not bring joy and happiness to the
system.

600x600 x 8 x 11 = about 4MB of memory

At 300 DPI, that's only 1MB, but if that moves things into swap space,
then performance will suffer rather terribly.

The speed of the parallel port shouldn't be a factor; I can get
several pages per minute out of my HP5L, which pumps out roughly 4
times as much data per page.

If we're talking about a 486DX/66, then that should be enough CPU to do
at least 2-3 pages per minute.  

- If there's 8MB of RAM or less on the system, that's a likely
bottleneck.  Without further information to go from, this is by far
the most likely cause of ill performance.

- If the CPU is less powerful than a 486DX/66, then that's a likely
bottleneck.  

- The parallel port is *conceivable,* but unlikely.  If it's the
problem, then there's something messed up with hardware.

I agree that "top" is likely to provide useful info; I'd speculate
that it will indicate that a couple megs of swap space are in use.
--snap--

I think, that I have got enough RAM (32MB). If I boot up into X, I
still have got >16MB available. The point is, that your HP5L has got a newer
version of HP PCL which uses compression algorithms. FYI: The CPU is an
Intel Pentium 60 (without FP error :-). I still suspect the parallel
port (of either the PC (unlikely) or the printer) to be the bottleneck,
since a straight "cat file.pcl >> /dev/lp1" took about 3 minutes for 900KB
which is 5KB/sec (see above).


--snip--
[rough translation since reply was in German language]
What kind of system do you have? Is the system load high? Could it be
that your printer is that slow? How fast does it work in DOS? You could
render it from gs into a file and print it in DOS.
Try the following as root
"time dd if=/dev/zero of=/dev/lp1 bs=1024 count=1024"
With this the printer shouldn't print anything and you would test the
transfer/processing time.
If it works faster in DOS and you have got a recent computer with ECP/EPP,
try my lp-fifo patch:
ftp://ftp.mathematik.th-darmstadt.de/pub/linux/bonnes/
--snap--

The system load isn't high (max. 1/3, so the computer is idle 2/3 of the
time). It could be that the printers parallel interface is that slow,
the mechanism is capable of printing 12 pages/minute. In DOS it's as slow as
in Linux. I tried the lp-fifo-patch, with no improvement.

I hope that's all open questions answered, so I still ask:
Has anyone got a clue how to improve parallel port speed (or has anyone got
a clue of how fast it should be - maybe from specifications or so)

Thanks to all who replied to this, Nils

--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


D 70197 Stuttgart                             Microsoft: They do it for money.

 
 
 

Speed up printing?

Post by Reinhold J. Gerha » Fri, 18 Jul 1997 04:00:00



>Hello,

>I've got a problem with my printer (a Toshiba PageLaser 12 model, it's approx.
>6 years old and emulates the HP LaserJet 500+ series). Almost anything I
>print is postscript and therefore converted to bitmap before printing (with
>the ghostscript ljetplus driver). The strange thing is the rather slow speed
>of printing. The transfer between my PC and the printer takes e.g. 8 minutes
>for 5 pages. Is it possible that the parallel line is so slow? After the
>printer has the page in its memory (2MB), it's only seconds until the page
>is printed - according to its documentation this model is capable of printing
>up to 12 pages per minute, therefore the link between PC and printer must be
>the bottleneck.

>Has anyone got a clue how to improve this? AFAIK the parallel port can be
>much faster, e.g. with Laplink (DOS program to connect to PCs via the
>parallel port) I saw transfer speed of approx. 160 KB/sec which would result
>in a maximum of about 12 to 13 seconds for the whole printer's memory to
>be filled.

I haven't had a printer that was fast enough to make a difference, but
I would make sure that the printer port driver was using interrupt
driven mode.

Let me know if this helps so I can add it to my "knowledge base."

Reinhold

--
Reinhold J. Gerharz          http://www.erols.com/rgerharz/
PGP Key at http://www.erols.com/rgerharz/pgp/public-key.asc