Hi, I'm struggling with a hard-to-pinpoint problem involving MPI - this is in relation to the johansensmall package and a pending update. I cannot yet give very much detail, but in a certain special context for a lower number of specified bootstrap iterations the thing runs fine, whereas when cranking up that iteration number, it basically fails with the typical obscure message from gretlmpi that an external command failed. So the algorithm and code per se do not seem to be wrong, or else it would always fail. My suspicion for now is related to some kind of memory limitation or a similar constraint. Is that conceivable? How would one check for that?

Am 03.11.2021 um 17:32 schrieb Riccardo (Jack) Lucchetti: > On Wed, 3 Nov 2021, Sven Schreiber wrote: >> >> I'm struggling with a hard-to-pinpoint problem involving MPI - this is >> in relation to the johansensmall package and a pending update. [...] > > Could it be that there is an extreme corner case, that occurs with > very small probability, that makes some command fail with error under > very extreme circumstances? However, when I run the thing sequentially with the same (high, but not that high, actually) number of replications, there is no problem. Therefore I believe it must be something more MPI-specific.

Am 04.11.2021 um 00:38 schrieb Allin Cottrell: > On Thu, 4 Nov 2021, Sven Schreiber wrote: >> Am 03.11.2021 um 17:32 schrieb Riccardo (Jack) Lucchetti: >>> Could it be that there is an extreme corner case, that occurs with >>> very small probability, that makes some command fail with error under >>> very extreme circumstances? >> >> However, when I run the thing sequentially with the same (high, but not >> that high, actually) number of replications, there is no problem. >> Therefore I believe it must be something more MPI-specific. > > Sven, why don't you send us (some of us, offlist if you wish) all > that's needed to produce the problem (if only sometimes)? > > There are tools we can use to investigate this, valgrind in particular. > Right, will do that eventually. Another thing that occurred to me is that the output from within an MPI block is notoriously problematic on Windows, IIRC. So I will do some testing on Linux to see if I can get some informative output from debugging statements or so.

Perhaps this is somehow due to gretl's attempt to spit out MPI output in real time on Windows, as Allin mentioned. So we can hope that this problem would be fixed as well, as soon as that attempt is abandoned. Still haven't had the time to test on Linux.