When distiller works it do folder in temp/Acrobat Distiller %version/any digit (in my case 00000D78) and put it temporary bitmap files for future pdf (f.e. G2j000003.d78). Then, when distilling has finished (99%-100%) distiller combine one pdf from multiple temporary files. We have 2 delays. 1 - write temporary file to temporary folder. 2 - read temporary file. I have pointed temp drive on ram disk (use SuperSpeed ramdisk plus) - 500Mb. It accelerated distilling about 50% (files which distilling 120 sec, distilling them in 60 sec). Its metod have insufficiency - very large distributives in one archive, like as acrobat X, which want extract to temporary drive, can use all space of ramdisk, and then get error.