[OS X TeX] microtype

[Peter Dyballa]

Am 09.08.2010 um 22:30 schrieb Manuel Pégourié-Gonnard:

> Do you really need so much ram?

One never knows! 4 GB could be sufficient. Presumingly all RAM disks  
won't consume more than 100 MB, one tenth of a GB. But then you have  
software like internet browsers running which consume more and more  
RAM because on 789 of the 801 open pages active elements, FLASH,  
animations are driving you insane, or you look at some videos, listen  
to internet radio, have to cache 1,000 non-free OT fonts. On the  
command line 'top -o cpu' and 'top -o reg' and 'top -o rsize' or 'top - 
o vsize' exist – or you use Activity Meter to see where your RAM goes.

> You could to just a little ramdisk for the tex compilation. Besides,  
> the time added by using microtype is probably spent doing  
> computations of line breaks, not disk I/O, so the ramdisk probably  
> won't help
> that much here...


Right! The microtype code is trying to find an optimal solution for  
each text line with a line break, maybe by successive approximation,  
i.e., many tries. This happens completely in memory, of course. The  
RAM disk for the book, and other interactive TeX work, is meant to  
save the SSD(s) from degradation by creating with every run this giant  
heap of temporary files, those which TeX and its packages need and  
those which do synchronisation between source and target. 1,200 runs,  
as George approximates, can be 10,000 write and delete actions,  
including also many alterations in the management layer of the files  
system (dates of file creation, modification, access time, updates to  
the directory's members; balancing the B+ trees which hold the leaves  
of file system entries in HFS+ – this action is necessary to guarantee  
an almost equal access time for accessing any leaf of the hierarchical  
tree), passing information to the disk's journal, giving Spotlight  
work...

You save a lot of CPU cycles when you do not keep a journal, do not  
feed Spotlight, do no balance a large B+ tree.

--
Greetings

   Pete

There's no place like 127.0.0.1
			– origin unknown