Changes (by Roland Haas):

The Formaline thorn, used for storing important information about a simulation in the simulation output, currently has some performance and size overheads which discourage people from using it. These should be reduced or mitigated to encourage people to use this important thorn.

This ticket is based on discussion in #1565.

Problems with Formaline:

• During compilation, Formaline stores the built source tree in a cactusjar.git repository. My impression is that this takes a lot of time on slow filesystems.
• During compilation, Formaline stores the whole source tree as tarballs in the executable. My impression is that this is also slow.
• The source tarballs output in the simulation output directory are often many times larger than the rest of the simulation, and cause a lot of overhead when transferring simulations for analysis. This might be improved by a better sync tool (simfactory 3?) which identified that tarballs were identical to those which have already been transferred, and skipped the transfer. I would like that the source tarballs are identical if the contents are identical, even if Cactus has been rebuilt. I think I observed that this was not the case (maybe a build ID is included?).
• As an aside: there is a message at link time that Formaline has finished doing something, but this is misleading; Formaline has other tasks which it does after this message is displayed; the wait for the final executable is not due solely to linking, but also to some archiving task of formaline.

Keyword:

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/1568/reduce-overhead-of-formaline