Phillip Susi <[email protected]> ha escrit: > After spending a day going out of my mind trying to figure out very > strange results from some performance comparisons I was doing, I finally > figured out that tar was cheating.
Perhaps it was not worth spending a day: tar operates this way since v. 1.11 at least (i.e. since 1996, if my memory serves me), and it is documented in the tar manual (see "6.1 Choosing and Naming Archive Files"). In particular the docs explain one of the reasons tar operates this way: When the archive is being created to `/dev/null', GNU `tar' tries to minimize input and output operations. The Amanda backup system, when used with GNU `tar', has an initial sizing pass which uses this feature. Regards, Sergey
