Question

我有以下R代码：

library(doParallel)
cl <- makeCluster(detectCores()-4, outfile = "")
registerDoParallel(cl)

calc <- function(i){
...
#returns a dataframe
}

system.time(
res<- foreach( i = 1:106800, .verbose = TRUE) %dopar% calc(i)
)

stopCluster(cl)

如果我从1：5运行该代码，它就会成功完成。如果我从106000 - 106800运行该代码，也会发生同样的情况。但是如果我运行完整的向量1-106800，甚至100000-106800（这些不是我正在使用的非常确切的数字但更好的可读性），它会失败，并显示以下错误消息：

...
got results for task 6813
numValues: 6814, numResults: 6813, stopped: TRUE
returning status FALSE
got results for task 6814
numValues: 6814, numResults: 6814, stopped: TRUE
calling combine function
evaluating call object to combine results:
  fun(accum, result.6733, result.6734, result.6735, result.6736, 
    result.6737, result.6738, result.6739, result.6740, result.6741, 
    result.6742, result.6743, result.6744, result.6745, result.6746, 
    result.6747, result.6748, result.6749, result.6750, result.6751, 
    result.6752, result.6753, result.6754, result.6755, result.6756, 
    result.6757, result.6758, result.6759, result.6760, result.6761, 
    result.6762, result.6763, result.6764, result.6765, result.6766, 
    result.6767, result.6768, result.6769, result.6770, result.6771, 
    result.6772, result.6773, result.6774, result.6775, result.6776, 
    result.6777, result.6778, result.6779, result.6780, result.6781, 
    result.6782, result.6783, result.6784, result.6785, result.6786, 
    result.6787, result.6788, result.6789, result.6790, result.6791, 
    result.6792, result.6793, result.6794, result.6795, result.6796, 
    result.6797, result.6798, result.6799, result.6800, result.6801, 
    result.6802, result.6803, result.6804, result.6805, result.6806, 
    result.6807, result.6808, result.6809, result.6810, result.6811, 
    result.6812, result.6813, result.6814)
returning status TRUE
Error in calc(i) : 
  task 1 failed - "object of type 'S4' is not subsettable"

我不知道为什么会收到此错误消息。不幸的是，我无法提供一个运行示例，因为我无法使用一些简单的代码重现它。单一工作失败了吗？如果是，我怎样才能找到哪一个失败？或者其他任何想法如何排除故障？

foreach-loop（R / doParallel包）失败，迭代次数很多

0 个答案: