Hi Duane, Duane Johnson wrote:
1. Is there a way to keep TeX in-memory (i.e. as a server or daemon process) so that it doesn't have to load and reload fonts and the environment? Our system makes repeated requests for typeset documents and we are wondering if there's a way to remove the overhead of re-running pdftex.
No, there is not (at least not using any of the 'stock' tex distributions). The one thing you could do is preload the fonts and modules you need into the format file, but setting this up is not completely trivial either.
2. Among the many different command-line TeX options, what might optimize for speed? I've done some rudimentary benchmarking and found that executing etex (without conTeXt) is much faster than texexec, and wondered if there is any advice in this area. Is there any way to shave off some of the overhead of using conTeXt?
You can only get rid of texexec and the .tuo|.tui handling if you do not need any kind of referencing at all in your document. If that is the case, you can run texexec with the --once switch, and that will help speed up run time quite a bit. texexec (without --once) will typically run the tex engine one time too many to make sure that all references are correctly resolved, so if you know behorehand how many runs are needed, you can speed up by eliminating that last run.
3. I've noticed that there is some kind of caching going on (tui/tuo files?) that helps speed things up after the first run. How can I best take advantage of this facility? What kinds of things will require TeX to start from scratch, vs. use some or all of this cached information?
The information in the tui file is not really cached, it is needed for cross references.
4. Are there any other areas I should consider when looking for ways to use TeX as an on-demand typesetting engine?
The best way right now to do general typesetting on demand using TeX is by creating asynchronous jobs. If that is not an option, then for the general case, you could consider paying (or hiring) a TeX developer to implement a daemon feature. Or you could out-source the whole affair: I know Pragma-ADE (Hans' company) has plans to set up a typesetting- on-demand service. I have found that in most specific cases, you can simplify by using either a dedicated format that runs on a bare-boned tex engine, or by just simply having people wait a while. Of course, it all depends on your actual situation. Best wishes, Taco